Saving the Monarch Butterfly

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Photo Credit: Stephanie Rathsack

 

According to recent data from overwintering monarch colonies, there are indications that both eastern and western monarch populations have declined by ~70% over the last 20 years—a dangerous figure when considering long-term survival of the species. These overwintering data provide scientists with information about survivors of each year’s migration to Mexico or California.  However, because monarchs are widespread throughout North America, it is extremely challenging to accurately understand and estimate how many individuals are present in the population before migrating. To help solve this problem the Monarch Joint Venture is partnering across Canada, the US and Mexico to engage citizen scientists in gathering data about the monarch late summer breeding population for one week (July 29th – August 5th). By collecting data from across the entire range during one small time window, citizen scientists from all three countries will help capture a snapshot of monarch breeding activity prior to peak migration.

 

Why a Monitoring Blitz?

Monarch butterflies are declining—this is a trend that has been seen over the course of several years, but it is still impossible to say just why it is occurring. It is easier for scientists to monitor monarchs in their overwintering sites due to their concentration in small areas. But this provides information during only a portion of the year, with several generations of butterflies occurring between each measuring period. With limited resources and a wide range to cover, it would be impossible for scientists to accurately measure monarch numbers throughout their breeding range. However, these numbers would provide new insight never yet considered, and would allow for a better understanding of why monarch populations are declining, and more importantly, what can be done to save them.

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Photo credit: Stephanie Rathsack

 

How can we help?

Anyone can help during the week of the International Monarch Monitoring Blitz. All you need is a location where milkweed is growing, and a way to record and submit the data you collect.  The blitz runs from July 29th to August 5th, and covers the entirety of the North American monarch butterfly range, including Mexico, the United States, and Canada. Depending on your site location, there are three locations where data will be collected:

 

United States: https://app.mlmp.org/Monitoring/AnecObservation.aspx

Canada: http://www.mission-monarch.org/

Mexico: http://www.naturalista.mx/projects/mariposa-monarca-en-mexico

 

In order to record data, participating citizen scientists should become familiar with the monarch life stages (egg, larval instars, pupa, and adult), and be able to commit a block of time to searching for them. The time spent searching can vary based on the participants availability, but can range between fifteen minutes and several hours.

In order to participate in this exciting event, River Bend Nature Center will be hosting a Monarch Larva Monitoring Project (MLMP) Training On Saturday, July 29th. Participants in this training will receive in depth information on the monarch butterfly including identification, life history, and rearing instructions. The remainder of the training will be an outdoor, hands-on data collection session. The information gathered during the course of this training will be submitted to the Monitoring Blitz, and participants will be able to use their knowledge to conduct their own data collection offsite.

 

Interested in participating in the MLMP training?

Seats are still available, but filling up fast! Pre-register online, over the phone, or in person in order to guarantee a spot.

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That Yellow Flower

While walking on the trails at River Bend, you may have enjoyed the sight of numerous summer flowers—in the prairies, forests, and ponds. And while these splashes of bright color are great for both nature lovers and pollinators alike, there is one species among them that acts as a bit of a villain. Chances are you’ve seen these plant before, but like any good villain, it stays well under the radar and disguises itself. Because of this, many people remain unaware of the danger. The plant in question is what’s known as “wild parsnip”. And if it sounds like something you’d find in the kitchen, you’d be right—the wild parsnip is a vegetable specifically cultivated for its large edible taproot (similar to carrots and other parsnips). It is a native plant to Europe and Asia, but after being brought overseas, it quickly escaped cultivation and took to forest and field with a vigor that outcompeted and overwhelmed most other native species of North America. In Minnesota, it is predominantly found in the southeastern region of the state, where it takes over prairies—sometimes to the point of turning them into complete monocultures. The resulting prairies resemble an “ocean of yellow”, as no other plants remain, leaving nothing visible except the bright yellow flowers on their tall stalks.

 

 

The Minnesota DNR describes parsnip as the following:

Appearance: Monocarpic perennial herbaceous plant (plant spends one or more years in rosette stage, blooms under favorable conditions, and then dies), 6″ high in the rosette stage and 4′ high on stout, grooved stems in the flowering stage.

Leaves: Alternate, leaf is made up of 5 -15 egg shaped leaflets along both sides of a common stalk; leaflets sharply-toothed or lobed at the margins; upper leaves smaller.

Flowers: Flat-topped broad flower cluster 2 – 6″ wide, numerous five-petaled yellow flowers; bloom from June to late summer.

Seeds: Small, flat, round, slightly ribbed, strawcolored, abundant take 3 weeks to ripen before they can reseed; viable in the soil for 4 years.

Roots: Long, thick, edible taproot.

 

wildparsnip

Unfortunately, the plants’ aggressive tendencies really is the least of it. Not only does it push other species out, but it actually poses a health hazard. The danger lies in the sap of the plant—the juices that flow through the stem and leaves and bring nutrients to all parts of the plant.

There are chemicals in wild parsnip sap called psoralens (speifically, furocoumarins) that cause what dermatologists call “phytophotodermatitis.” That means an inflammation (itis) of the skin (derm) induced by a plant (phyto) with the help of sunlight (photo). When absorbed by skin, and then exposed to the sun, furocoumarins are energized by ultraviolet light (present during BOTH sunny and cloudy days) causing them to bind with nuclear DNA and cell membranes. This process destroys cells and skin tissue, though the reaction takes time to produce visible damage. In less severe cases, affected skin reddens and feels sunburned afterwards. In more severe cases, the skin reddens first, then blisters rise, with some potentially even being quite large. And for a while the area feels like it has been scalded. Places where skin is most sensitive (arms, legs, torso, face, neck) are most vulnerable. Moisture from perspiration also speeds up the absorption of the psoralens.

 

According to the Wisconsin DNR, concerning the burns:

 

  1. Everyone can get it. Unlike poison ivy, you don’t need to be sensitized by a prior exposure. Wild parsnip causes a non-allergic dermatitis that can occur with the right combination of plant juice and sunlight.

 

  1. You can touch and brush against the plant – carefully – without harm. Parsnip is only dangerous when the juice gets on skin from broken leaves or stems. Fair-skinned people, however, may be extra-sensitive to tiny amounts of juice.

 

  1. Wild parsnip’s “burn” is usually less irritating than poison ivy’s “itch.” Generally, wild parsnip causes a modest burning pain for a day or two, and then the worst is over. The itch and discomfort from poison ivy, in contrast, can drive people crazy for a long time.

 

At River Bend Nature Center, wild parsnip has become a large problem—it dominates the southern prairies, and creeps up into the edges of trails where the largest danger comes from unaware visitors (especially young ones) picking the attractive flowers. To help reduce this risk, the staff and volunteers of River Bend have been removing parsnip as it appears along trails in order to keep it “out of reach”. In addition to this, prairie burns are conducted, as well as organized pulls and cuts. However, due to the number of plants and the large area they cover, it is often a slow process which is difficult to see progress in. For this reason, River Bend relies on the help of volunteers and other members of the community. We rely on them to be aware of the plant, heed warning signs posted along trails, and to also help educate others. We also rely on their assistance with the removal of the plant itself.

If you are interested in land restoration and the removal of parsnip, there are several upcoming opportunities for you to get involved:

 

Restoration Work Day – Parsnip Pull

Ages 10 and up. Free!
Wednesday, July 12th, 2017, 3:00pm – 5:00pm
Sunday, July 23rd, 2017, 10:00-noon

Join us for a restoration-themed work day.  Twice a month we’ll head out onto the River Bend property to remove non-native invasive species and work to restore native habitat.  You’ll learn restoration skills at River Bend that you can take home and implement on your property!  No experience needed, no commitment required.  Come once or come for them all!

This month’s program will be focused on the removal of wild parsnip. But the Restoration Program is ongoing through the summer on the 2nd Wednesday of the month from 3:00pm – 5:00pm, and the 4th Sunday of the month from 10:00am – 12:00pm, with a different focus each meeting.

To register, call or visit our website: https://riverbend.z2systems.com/np/clients/riverbend/event.jsp?event=1676

 

Growing up Monarch – 4

“Growing up Monarch” is an on-going segment in the River Bend blog that follows the lives of several monarch butterflies as they grow from egg, to caterpillar, to chrysalis, to adult. We’ll be updating with photos and fun facts and observations throughout the summer!

 

Time flies—literally—when you’re caring for butterflies. And those caterpillars who were smaller than pencil tips just a month ago are now full-fledged and flying strong. However, this transformation did not occur over night. When last we checked in, (on Monday, May 12th) all three caterpillars had successfully pupated, and all three were safely relocated to larger enclosures for observation. The chrysalises were also studied with a hand lens to determine their gender. This can be a difficult stage to sex monarchs, and it is also the earliest you can sex them without having to kill and dissect them.

 

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Females can be identified in chrysalis by the line intersecting the upper abdominal segment. (Lower image) Males lack this line. (Upper image) Photo credit: Stephanie Rathsack

 

After looking closely at our three individuals, it was determined that the first (the largest caterpillar) was female, while the other two remaining chrysalises were male. While this will make little difference in the rearing process, it makes for interesting data and will allow for easier planning of potential breeding.

 

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By the afternoon of Monday the 19th, the two older chrysalises had started to darken—revealing the colorful patterns on the butterfly’s wings. Photo credit: Stephanie Rathsack

It takes approximately ten days for the chrysalises to mature to adult butterflies, and during this time period, very little occurs that is visible to the caretaker. The chrysalis will remain green and entirely stationary during the whole length of the 10-14 days, and only in the last twenty-four hours will a noticeable change begin to take place.

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Just before emerging, the chrysalis darkens immensely—becoming so transparent that the butterfly and all details of its anatomy and coloration become visible. Photo credit: Stephanie Rathsack

 

When the chrysalis darkens, everything becomes a waiting game. It takes less than a minute for a stationary (almost dead looking) chrysalis to emerge s a living breathing butterfly. With such a short window of time to watch for, even short lapses in concentration can cause the viewer to miss the opportunity. And yet, this can take hours. There is no clear indication how long it will take for a butterfly to emerge from her chrysalis. One the red of the wings is visible it could take anywhere between minutes, up to the length of a day. And so being able to witness the “eclosure” is a matter of patience and also of luck. The author spent just over two hours waiting for the second chrysalis to eclose, as the first (the female) had emerged overnight. Rather than staring for the entirety of those two hours, the author did risk moving back and forth between tasks, hoping to luck that the timing would work out. And after several hours in the early afternoon, a telltale, tiny, almost plastic-like “crack” became audible, and that was the only sign needed to know that something amazing was about to take place.

 

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A timelapse of the second butterfly as he emerges from his chrysalis. The entire process takes less than a minute to occur. Photo credit: Stephanie Rathsack

 

With what can be imagined as great strain, the butterfly pushes his legs and head against the walls f the paper thin chrysalis, which breaks along two lines—creating a piece that may be lifted up, similar to a door. This gives the butterfly an exit through which he can pull himself out by grabbing the chrysalis with his front legs and tugging hard. It’s amazing to see the butterfly come out of the chrysalis, as he still looks very chrysalis-shaped, despite the clear anatomical changes (wings, for example). His abdomen however is still the large bulbous shape of the top end of a chrysalis, and it falls down dramatically heavy once free to do so. Once the abdomen has dropped, it’s only seconds before the wings follow suit and suddenly the entire butterfly is visible—small, shrunken, and damp, but visible. He clings for life upside down to the chrysalis which had once been a part of himself, like a kid on the monkey bars. Hanging in this manner allows hemolymph (the insect alternative to blood) to flow from the abdomen into the wings, this “pumping” them up to their full size. As this occurs, the wings will enlarge and the abdomen will shrink. He also seems to experimentally flick out his proboscis—the new mouthpart with which he will feed with for the rest of his life. It’s much different than the leaf-cutting mouthparts of a caterpillar. Just minutes after emerging, the proboscis is actually split in two, and will fuse together into one apparatus while the monarch hangs. This “zippering” of the two halves is essential as it is their merging that creates the hollow “straw-like” central cavity through which the monarch’s entirely liquid diet will be “slurped”.

The process of drying takes much longer than eclosing, and in fact, for the first twelve hours, a monarch is generally unwilling or unable to fly or feed. But even after a half hour, he begins to look more full-formed, though still remains vulnerable. It’s important that they are not touched or moved during this sensitive time period, as this can damage their development, and a fall at this stage could even prove fatal.

 

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Both the male (left) and female (right)  hanging from their respective chrysalises as seen at 1:22 pm on Tuesday June 20th. The third chrysalis (middle) is not yet ready to emerge, and would not eclose until the next day. Photo credit: Stephanie Rathsack

 

After being left to their own devices until completely dry, the next step in the rearing process will begin: keeping and caring for adult butterflies. Generally this is an unnecessary step, and amateur or beginner monarch keepers should attempt this with the greatest care.

 

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A monarch clings to his now empty chrysalis with hooked feet. The ring of gold is somewhat dimmed now, which suggests that its metallic coloring was due in part to yellow pigments (still visible on the empty chrysalis) and the concave curves of the butterfly inside (now lacking after the butterfly emerged). Photo credit: Stephanie Rathsack

 

Adult monarchs are notoriously difficult to maintain, unlike their younger counterparts. They require larger spaces, proper lighting, and appropriate food daily. The first step in caring for them, actually involves a bit of science. The health of the butterflies needs to be determined, as rearing infected monarchs can prove detrimental for the species if allowed to spread the disease. In order to do this, a “Tape test” is administered—which should NOT be attempted without prior experience. It involves taking a piece of clear tape and gently pressing it to the sides of the butterfly’s abdomen—removing some scales in the process. This does not harm the butterfly. The tape is then placed on white paper and observed under a microscope.


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The scales on a monarch’s forewing each have a distinct color which makes up the bright pattern which warns of poison. Photo credit: Stephanie Rathsack

 

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To safely handle a monarch, hold all four wings together and pinch gently on the top ridge where the wings are most rigid. Photo credit: Stephanie Rathsack
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Scales from a monarch’s abdomen are visible on the piece of clear tape. Photo credit: Stephanie Rathsack

 

 

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Looking at the scales under a microscope to determine the health of the monarch butterfly. Photo credit: Stephanie Rathsack

 

When viewing the scales under the microscope, what you’re searching for are small spores from the obligate protozoan parasite Ophryocystis elektroscirrha which uses both the monarch and the queen butterfly as hosts. Infection from this protist can cause deformity in large amounts and even prevent the monarch from emerging from its chrysalis.

 

 

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The spores of OE are very small in comparison to the butterfly’s scales.
Photo credit:
http://monarchparasites.uga.edu/whatisOE/

 

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The third chrysalis emerged on the afternoon of the 20th. Photo credit: Stephanie Rathsack

 

 

After testing, it was found that all three of River Bend’s monarchs were healthy and free of parasites and were placed in a large free-flying enclosure where they will feed actively every day and also begin courtship before laying eggs and starting the life cycle all over again.

 

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The female and one of the males perform pre-mating courtship behaviors. Photo credit: Stephanie Rathsack

 

Want to learn more?

 

Stop by our interpretive center any day during the week to talk to a naturalist and see the monarchs for yourself! The building hours are as follows:

Wed-Fri 8:00-4:30

Sat 9:00-4:30

Sun 9:00-2:00

 

Interested in getting more involved?

 

River Bend will be offering MLMP trainings to teach interested members of the community to become certified MLMP volunteers! Monitor at home or at River Bend, and help save this amazing insect from extinction.

Register online to attend the training scheduled for July 29th from 1:00-4:00pm.

For more information, see our website at: http://www.rbnc.org/

Turtle Crossing

It’s hard to believe that it’s already the middle of June, but signs of summer are everywhere! Mulberries are putting out their berries, early flowers are going to seed, and at every pond around River Bend, female turtles have been leaving the safety of the water to make the long trek through woods and fields in order to lay their eggs. Unfortunately, sometimes, these treks become even more dangerous because of the presence of humans. While it’s not unusual to find turtles walking far from the nearest source of water during laying season, as human activity increases it’s becoming far more common for turtles to walk further than average. Pollution, lack of food, habitat destruction, among other stresses, all contribute to driving turtles of all species to travel far to find nesting sites.

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A large snapping turtle crosses Rustad Road. Photo credit: Stephanie Rathsack

At River Bend, the species most frequently encountered are painted turtles and snapping turtles. While at the nature center, you’re most likely to encounter a nesting turtle of either of these species as she moves from the water to the nesting site as this will often require her to cross roads and other paths. This can be extremely dangerous as not all drivers will see the turtles in time to stop, and turtles are not fast enough to get out of the way. This results in countless fatalities every year across the state, and may also be contributing to the decline of several species. Unlike deer, raccoon, or other animals frequently hit along roads, turtles do not rear their young or protect them in any way, and thus hatchlings have a very high mortality rate. Because of this, even the death of one adult individual can be catastrophic for the species as a whole.

That’s great, but how can I help?

The best way we can help turtles is by being aware. Many road collisions can be prevented if drivers maintain the posted speed limits and remain aware of their surroundings. Drivers should stop if safe to do so when a turtle is in front of their vehicle, but should avoid swerving violently or any other action that may prove dangerous to others in the area.

A turtle is walking across the road. What should I do?

As stated above, if driving a vehicle, stop if safe to do so, and if time and traffic allows, allow the turtle to complete its journey on its own. Alert other drivers of the crossing turtle as well. If you’re on foot, or if you do not believe the turtle will be able to safely cross on its own, the turtle may be carried across to safety, but several factors should be kept in mind:

  1. Follow the line of travel. Always carry a turtle in a straight line in the direction it was originally traveling. If you place a turtle on the wrong side, she will merely turn around and cross the road again. Place the turtle off the road, but no further. While it may be tempting to bring the turtle to the nearest body of water, it’s bet to let instinct take the turtle to where it needs to be, rather than interfering.
  2. Handling with care. Turtles should be lifted carefully by the sides of the shell (never by the tail or a foot!). The only exception is with snapping turtles and softshell turtles—both these species have a reputation for biting without excessive provocation, and their bites can be very strong. If you encounter one of these species, call River Bend staff for assistance. After handling any reptile, be sure to wash your hands with soap and water, all reptiles have the potential to carry salmonella.
  3. Document your find. Help scientists by recording crossing and mortality areas by participating in the Minnesota Turtle Crossing Tally & Count Project: http://www.herpmapper.org/content/pdf/mn-turtles-and-roads-project.pdf

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Parking lots can be a daunting cross for even the largest turtles. Photo credit: Stephanie Rathsack

I want to help a turtle across the road, but I don’t think it’s a painted turtle or a snapping turtle.

Minnesota is home to eight species of turtle, two of which are quite rare: the blanding’s turtle, and the wood turtle. These two species are terrestrial, and spent their lives out of the water. They are both listed as protected throughout Minnesota, and therefore it is illegal to handle or possess either without special permitting. If you do not recognize the species, call for River Bend staff assistance to have the turtle identified.

I think I found a turtle nest.

It’s not uncommon to find turtle nests, though they’re most often discovered after the hatchlings have already left, as their will be a sizeable hole in the ground with remnants of eggshells. If, however, you have found a nest (either having witnessed the female laying, or by other means) the most important thing to do is leave it alone. Do NOT attempt to relocate the eggs or stop the female from laying. If the nest is in a location that appears unsafe on River Bend property, contact River Bend staff for assistance. If the nest is on your property or elsewhere, the DNR may be contacted to help guide you through what to do.

I want to keep and observe the nest.

If on your own property, a turtle nest can be an exciting opportunity for observation. However, turtle nests are often subject to predation by mink, raccoons, and other scavengers, and these animals are often attracted by the scent of humans. Do not excessively visit the nest. Instead, place a motion sensitive camera or view from a distance. If you’re concerned about predation, wire fencing can be placed around and over the nesting site to keep other animals out, but be sure to check back frequently in order to let the baby turtles out when the time comes.

IMG_20170612_124123Some species have already hatched–such as this nest discovered earlier last week.
Photo credit: Stephanie Rathsack

Interested in learning more about the turtles of River Bend and Minnesota? Stop by our interpretive Center Saturday, July 8th for an Animal Ambassadors program and a chance to meet our turtles up close and personal. More information can be found on our website at http://www.rbnc.org/ .

Growing up Monarch – 3

“Growing up Monarch” is an on-going segment in the River Bend blog that follows the lives of several monarch butterflies as they grow from egg, to caterpillar, to chrysalis, to adult. We’ll be updating with photos and fun facts and observations throughout the summer!
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All three River Bend caterpillars are 5th instars. Photo credit: Stephanie Rathsack

 

Another week has gone by and our three resident monarchs have grown an immense amount! When last we checked in, they were all what is known as 4th instars, meaning that they had shed their skins three times, and would have several distinct features: bold yellow triangles on their heads, “chunkier” bodies with dark banding, and long front tentacles (antennae) that go beyond their head capsules. By Friday the 9th all three caterpillars had shed once again and become 5th instars.

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When shedding and during windy days a monarch caterpillar will produce silk (similar to spiders) in order to anchor itself to the leaf. Silk is one of the strongest natural fibers and it’s thought that pound for pound it is stronger than steel. Photo credit: Stephanie Rathsack

 

As 5th instars our caterpillars are in their final stage as larvae. This means that within just a few short days they’ll be preparing to pupate. The 5th instar stage is marked as being the largest of all the stages, and their front tentacles will be extremely long, becoming noticeably “droopy” past the head capsule. Another key feature though sometimes more difficult to distinguish is a velvety appearance to the black stripes along their bodies.

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The black stripes on 5th instars are very large and almost velvety in appearance.
Photo credit: Stephanie Rathsack

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The front tentacles of 5th instars are extremely long and are distinctively droopy towards the ends. Photo credit: Stephanie Rathsack

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The facial markings of 5th instars are bright and clearly visible. Note the large triangle in the center. Photo credit: Stephanie Rathsack

 

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Between May 30th (2nd instar) and June 10th (5th instar), just 12 days apart, our caterpillars have dramatically increased in size. Photo credit: Stephanie Rathsack
And while the caterpillars at this stage are very close to completing their time as larva, they still have a little bit of growing to do and a little bit of weight to gain and so of course that means…more eating! They have continued to feed almost nonstop (except to molt and produce frass). However, this constant feeding is noticeably slowing compared to their feeding habits as 3rd and 4th instars. More often they can be seen resting on the leaves—perhaps preparing their bodies for the big changes that are about to occur. In fact, scientists have dissected caterpillars at this stage to discover that several butterfly organs are already starting to form. And so even though these changes are not visible to us, we can imagine the amount of energy it would take to go from an animal that crawls on the ground to one that is capable of flying up to 2,000 miles (anyone would need a nap!).
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Although nearly full size, the 5th instar caterpillars can still be seen feeding fairly frequently. Photo credit: Stephanie Rathsack

With three caterpillars sharing an enclosure it’s never a surprise when overnight entire leaves will be consumed—not a single scrap being left (not even the stems)—leaving an empty tank with three very hungry caterpillars looking for seconds, thirds, and fourths. For this reason, rearing monarchs can be a very demanding job, requiring frequent trips to collect fresh leaves no matter what the weather may be.

 

 

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Being larger doesn’t make you invincible. While 5th instars are notably more bold and more likely to explore their environments than their smaller counterparts, they will still consistently take shelter on the undersides of leaves, perhaps to prevent being spotted by predators. Photo credit: Stephanie Rathsack

 

And while rearing caterpillars can be an immense amount of work, it is also a very rewarding process, allowing you to view them at every stage, and also witness infrequent or short-lived behaviors that would be difficult to spot in the wild if not impossible. One such behavior that the author witnessed on Saturday the 10th was especially interesting. With three large caterpillars all relatively close together it soon became apparent that this species is by no means gregarious, and has no instinct for companionship. Quite the opposite actually—they are notably aggressive towards those of their own kind, behaving in a manner that you would expect to see exhibited towards potential predators and not towards other caterpillars (who are so similar in size and appearance they may as well be identical). When one caterpillar wandered too close to its neighbors, close enough to brush up against them, the former responded by violently thrashing their head towards the intruder. This motion was repeated several times with a clear “back off” message similar to that of a lunging dog, but the recipient of these “attacks” appeared completely oblivious and merely continued on its way. Eventually the trespasser moved along far enough, and it would seem that touch was the catalyst for this behavior, for as soon as contact was removed, all normal activities of feeding resumed as though nothing had happened.

 

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The caterpillar in the center wandered too close to its neighbors and was punished for doing so by both individuals on either side of it. When touched, the caterpillars will rear their heads and lunge at the intruder—perhaps to drive them off.
Photo credit: Stephanie Rathsack

 

It’s likely that this behavior is completely instinctual, rather than decision-based. It would seem that caterpillars are “wired” to rear up at unexpected physical stimuli, that is, to throw themselves at things that touch them. This would effectively make them look larger (and probably less appetizing) to would-be predators. It’s behaviors such as this that allow these caterpillars to survive their long lives in this vulnerable stage. For while they are toxic, not all animals have learned to associate the bands of black, yellow, and white, with danger, and will therefore feed on monarch larva before finally understanding that they all are unpalatable. This defensive behavior may also tie in with the necessity to roam. As the caterpillars continue to grow they will soon cease feeding altogether, just as they had when preparing to molt. This time however will be different, and the caterpillar will be searching for a very special location.

 

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The large tentacles of 5th instars may be useful in sensing the environment, especially when exploring an unfamiliar location. Photo credit: Stephanie Rathsack

 

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When large enough, the caterpillars will stop eating and begin to move around more—even leaving their host plant entirely in search of a safe place to pupate.
Photo credit: Stephanie Rathsack

 

It’s important that the location chosen is perfect—protected both from the elements as well as from predators, as the next stage, the chrysalis, is by far the most vulnerable of all its stages. As a chrysalis, the monarch will be completely unable to move or defend itself in any way as it goes through the difficult transformation into butterfly. For this reason, it is immensely difficult to locate monarch chrysalises in the wild. They are often not placed on milkweed plants, and also camouflage well with their surroundings.

 

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Over the course of approximately two to three weeks, a monarch caterpillar will increase its total mass 2000 times. Seen clearly in comparison between a 5th instar and a newly hatched 1st instar.
Photo credit: Stephanie Rathsack

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A 5th instar puts on a lot of weight in order to pupate—and their body segments will become especially pronounced. Photo credit: Stephanie Rathsack

 

Once they have found the perfect spot, the caterpillar must do several things in order to pupate. First, it must start laying down a mat of silk. It would have done this every time it molted as well, as this mat of silk provides a surface on which to grip and adds extra stability. This time the mat is noticeably larger and thicker. The caterpillar will also create a small wad of silk that is much thicker—this will be the point at which it attaches itself during pupation. Caterpillars produce silk similarly to spiders—through an organ known as a “spinneret”. On monarchs it is located beneath the mouth. Silk begins as a liquid produced in the salivary glands after which it is excreted through the spinneret. Upon coming into contact with air, the liquid silk will turn into solid strands which the caterpillar may then place down. Throughout its life as a caterpillar they retain this ability, and it is most often used as a mat when molting, or as a “life line” if the caterpillar were ever to fall off its host plant. After pupating they lose the spinneret, and also the ability to create silk as it will not be needed in the adult stage.

 

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The silver-white strands of silk are clearly seen crisscrossing underneath the caterpillar. Once finished laying down this mat, it will then begin work on a silk pad, visible here as a small white ball located beneath the caterpillar’s head. Photo credit: Stephanie Rathsack

 

 

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Once the silk pad is completed, the caterpillar will turn around and grip the pad with its back prolegs. Photo credit: Stephanie Rathsack

 

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As of the afternoon of June 11th, both larger caterpillars were in the distinctive “J” of pre-pupation, while the third, smaller caterpillar, was still feeding.
Photo credit: Stephanie Rathsack

Upon completion of its silk pad, the caterpillar will use this as a gripping point as it moves into the next stage of pupation. In order to form a chrysalis, the caterpillar will drop its head so that it will be hanging upside down by its back prolegs.  They will remain like this for anywhere between 10 and 24 hours, completely unmoving and unchanged—at least on the outside. It couldn’t be further from the case inside. As the hours tick by, the caterpillar will start to move again, appearing to almost be doing sit ups as it will move its head up and down repeatedly. Next, it will appear to grow tired of this movement and hang more loosely, looking less like a J and more like an I. At this point, if you look at its front tentacles carefully, you may notice that they appear shriveled—this is a sign that pupation will soon occur, as there is no longer any “caterpillar” inside that part of its body any longer, and it is ready to molt for the last time. The last sign will be a small tear along the caterpillar’s back, right behind the head. This tear will reveal the bright green of the chrysalis underneath and will grow larger and larger as the skin is worked upwards. This entire process once the skin splits takes just about a minute to complete, so viewing this phenomenon takes not just patience, but also luck and good timing. As the skin continues to come off, more of the chrysalis will be revealed, and many butterfly features will be clearly visible—such as the wings and antennae. When the skin has reached the rear legs, the chrysalis will start twisting around in circles—this serves a duo purpose: one, to remove the old skin completely, and two, to firmly attach itself to the pad of silk. This transition needs to occur quickly, as the caterpillar no longer has back legs to hold onto the silk with. Instead, it must use the cremaster (the black peg on the chrysalis) by hooking it onto the silk. The twisting motion increases the number of strands that hook on, similar to how Velcro works.

By the evening of the 11th both larger caterpillars had pupated and the smallest of the had begun work on its silk pad. Overnight, the smallest caterpillar pupated as well.

 

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The two first chrysalises were carefully removed from where they had originally pupated in order to be relocated. If you raise your own monarchs, do NOT attempt this without prior experience. Photo credit: Stephanie Rathsack

 

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The morning of Monday the 12th both chrysalises were safely transferred to a new location for easier observation. The 3rd chrysalis had pupated overnight and was still too soft to move. Photo credit: Stephanie Rathsack

 

Want to learn more?

Stop by our interpretive center this week to talk to a naturalist and see the monarchs for yourself! The monarchs will be available to view:

Mon-Fri     8:00-4:30
Sat              9:00-4:00
Sun             9:00-2:00

 

Interested in getting more involved?

River Bend will be offering MLMP trainings to teach interested members of the community to become certified MLMP volunteers! Monitor at home or at River Bend, and help save this amazing insect from extinction.

Register online to attend the training scheduled for July 29th 100-4:00pm.

For more information, see our website at: http://www.rbnc.org/

Growing up Monarch – 2

“Growing up Monarch” is an on-going segment in the River Bend blog that follows the lives of several monarch butterflies as they grow from egg, to caterpillar, to chrysalis, to adult. We’ll be updating with photos and fun facts and observations throughout the summer!

 

It’s been a week since we last looked at the monarchs that River Bend is raising, and a lot has happened in those seven days! In the life of a caterpillar, change happens quickly, and with just about a month to go from a tiny egg to a full-fledged butterfly, there’s no time to waste in putting on those growth spurts, and our resident royalty has been doing just that.

1The smallest of the three caterpillars remains a “1st instar”, though its larger cage mates have already molted. Photo credit: Stephanie Rathsack

Ever since day one, these larvae have been professional eating machines—spending most of their day chowing down on the provided milkweed leaves. You’ll recall from our last post that monarch larva feed exclusively on milkweed—refusing any other offered vegetation. They do, however, start their lives off with a slightly different meal: their own eggshell. And unfortunately, in some cases, the eggshells of other caterpillars. Such was the case for our River Bend monarchs.

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Skin clings to the back of a newly molted 2nd instar caterpillar.
Photo credit: Stephanie Rathsack

Last week we had a total of three caterpillars and one ready-to-hatch egg, but since then we’ve dropped by one, as one of the caterpillars made a meal out of the last egg before it could hatch. This cannibalistic behavior may be another reason for why female monarchs lay only one egg per plant, as the larvae appear to have no qualms about siblicide. With that being said, we now have a grand total of three healthy caterpillars, and all danger of competition between them has passed. Since then, they have continued to feed voraciously. They no longer eat in the characteristic circle pattern of newly hatched caterpillars, instead they now chew all the way through the leaves, creating small holes as they do so.

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While nearly the same size, the caterpillar on the left is a recently molted 2nd instar, while the caterpillar on the right is still a 1st instar, preparing to molt—indicated by the dropped head capsule and the white silk holding it in place. Photo credit: Stephanie Rathsack

With all that eating, it’s no surprise that they’ve already increased in size. As of Tuesday May 30th, one caterpillar had already molted into its 2nd instar stage, with another preparing to do so as well.

4Rearing its head may help this 3rd instar navigate its surroundings. Photo credit: Stephanie Rathsack

The third caterpillar is slightly smaller, and took longer to be ready to molt its skin. This molting, or “ecdysis” as it’s referred to by scientists, will occur several times during the caterpillar stage and can be predicted by several behaviors as well as physical changes—the most obvious being a lack of appetite. Our caterpillars would stop eating and stop moving completely as they prepared to shed their skin. Prior to molting, the caterpillars will lay down a layer of silk that helps hold them in place.

5Upon completing its molt, the caterpillar’s new skin is soft and light colored—obvious in this photo as seen by its yellow head and legs. These parts will darken over the next few hours, but until then the larva is at its most vulnerable, similar to a crab without its shell. Photo credit: Stephanie Rathsack

By Saturday, June 3rd, all three caterpillars had shed twice, and were officially “3rd instars”—the largest even preparing to molt again to become a 4th instar.

The smallest of the three caterpillars was once again the last to prepare to molt, though on Saturday it was in search of a location to do so as it roamed its habitat, occasionally rearing its head up—which may assist sensing its environment, as well as start loosening the older skin and head capsule.

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Two third instar caterpillars, with the individual in the foreground preparing to molt. Note the dropped head capsule, with the newer, lighter colored skin above it. Photo credit: Stephanie Rathsack

It takes caterpillars roughly two weeks to go from 1st instar to chrysalis, and our three caterpillars, having hatched on Friday, May 26th should be preparing to pupate late this upcoming weekend. They still have some growing to do however, and will continue feeding every day in order to do so.

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“Frass happens”
This 3rd instar expelled some of its waste during observation. Caterpillar poop is known as “frass” in the scientific world, and this caterpillar displayed an odd behavior as it promptly turned around, and picked the frass up, moving it around several times before leaving it behind.
Photo credit: Stephanie Rathsack

Today, Monday the 5th, all three caterpillars have shed their skin and are officially 4th instars. They have bold stripes along their bodies, large banded heads, and front antennae that droop down past their head capsules—all key characteristics of 4th instar caterpillars. Within the next few days they’ll shed again to become 5th instars, and then finally, they will shed their skin a final time in order to transform into a chrysalis.

 

unnamedA view of all three caterpillars as viewed on Monday, June 5th. All three are considered “4th instars” at this stage, despite the differences in size. Photo credit: Stephanie Rathsack

 

Want to learn more?

Stop by our interpretive center this weekend to talk to a naturalist and see the monarchs for yourself! The monarchs will be viewable  as follows:
Fri 8:00-4:30
Sat 9:00-4:30
Sun 9:00-2:00

Interested in getting more involved?

River Bend will be offering MLMP trainings to teach interested members of the community to become certified MLMP volunteers! Monitor at home or at River Bend, and help save this amazing insect from extinction.
Register online to attend the training scheduled for June 10th from 1:00-4:00pm.

For more information, see our website at: http://www.rbnc.org/

Growing Up Monarch – 1

In 2014, monarch butterfly populations reached an all-time low—having declined approximately 90% in the last twenty two years. This sparked a Nation-wide effort to help preserve and protect the once common insect and its incredible 2000 mile migration. Now, studies have shown a potential rise in numbers, ending with the 2015-2016 annual overwintering count which reported the highest population since 2009. This increase in population was predicted by experts due to ideal weather conditions during the breeding months, as populations are widely effected by changing weather. For example, in 2002, a single storm killed an estimated 500 million monarchs. Statistics like this solidify the fact that monarchs need a very large population size in order to be resilient to threats. In other words, there must be a surplus of individuals in order for the species to endure.

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In addition to weather, monarch butterflies face numerous threats to their overall survival, many of which involve humans. The true difficulty in protecting this species also lies with the fact that it spans across three countries and two distinct “sites”. Monarch butterflies require a breeding and feeding site as well as an overwintering site. In search of these sites, a monarch butterfly may travel from Canada through the United States to Mexico. This large expanse of land covered makes it difficult to protect the entire range. These two specific sites also present their own unique threats; for example, loss of milkweed due to new agricultural practices. Monarch butterflies go through a 3-5 generation cycle during the breeding season, and the caterpillars feed exclusively on milkweed. It has been shown that nearly half of the migrating monarchs are produced in the U.S. “corn belt”, and yet with new agricultural practices, the milkweed found in this region is being eradicated, particularly due to modified crops that are herbicide-tolerant, allowing for wide-spread use of chemicals that eliminate all other vegetation.

Even after surviving through the summer months, monarchs face a whole new set of challenges, including the actual act of migrating up to 2,000 miles (a daunting task, even when you’re not an insect that weights half a gram). Once at the wintering grounds, the butterflies rely entirely on the microclimate provided by the forests of central Mexico. Due to this unique need, monarch butterflies are at special risk throughout the winter. One of the largest threats is deforestation (both legal and illegal logging practices) which removes roosts, as well as threatens the delicate microclimate. However, the nature of how the monarchs overwinter is a risk in and of itself. The butterflies are concentrated into one small region which makes the entire population vulnerable to a single storm or any other disaster such as fire and disease. Ecotourism also poses a threat to the integrity of the winter refuge, along with many other pressures. In short, people compete with monarch butterflies, not only for space, but also for food and water, and the needs of the people who live in this region must be balanced with the needs of the butterflies. And while many of these difficulties may seem far away and difficult to manage, especially for those living in the Midwest, there are many ways that anyone can make a difference in protecting monarch butterflies. The first and potentially most impactful way you can make a difference is through education. Many people are still unaware of the plight of the monarch butterfly, and even more don’t fully understand the effects of their actions, such as removing milkweed or spraying herbicides/insecticides. For this reason, it is important to not only remain up to date on developing research, but also to educate others as well. This can be as simple as planting a native plant garden in your yard, participating in citizen science, or attending one of many monarch butterfly events throughout the nation. River Bend Nature Center will be hosting one such event on June 10th—a program offering community members a chance to become certified citizen scientists for the Monarch Larva Monitoring Program. During the course of the program, participants will learn details on monarch life history, including their migration, before heading outside to get hands-on experience in searching for monarchs and collecting data.

River Bend will also be playing host to several monarchs in the Interpretive Building as we watch them go through their incredible life cycle. Stop in to see them transform from egg, to larva, to pupa, to adult, and finally, if you’re lucky, help us release them back into the wild!

Our current monarchs were laid on Tuesday, May 23rd. Adult female monarchs in Minnesota in late spring are most often “2nd generation” butterflies, meaning that they are the children of those individuals who overwintered in Mexico. They were hatched in the southern states and flew the remainder of the migration to the northern states and Canada where they breed, lay eggs, and die. This would make the eggs we have “3rd generation”, or the grandchildren of the butterflies in Mexico.

1 egg layingWhen laying their eggs, a female will cling to a leaf and bend her abdomen underneath so that the egg will be on the bottom side. This placement would potentially help moderate heat and moisture, and also reduce predation rates. The female will generally only lay one egg per plant in order to decrease competition between larva, but multiple eggs per plant are not unheard of if multiple females visit the same plant.
Photo credit: Stephanie Rathsack

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Monarch egg on the underside of a milkweed leaf. When the eggs are first laid, they’re often a creamy white, and will become more yellow in appearance as they age.
Photo credit: Stephanie Rathsack

The eggs are minuscule in size, and it takes a trained eye in order to spot them. However, they can be easily identified as monarchs by their pointed top and the distinct ridges that run vertically all around the egg.

It will take about four days for the eggs to be ready to hatch, though the process may be sped up or slowed down by temperatures. Colder temperatures will slow down the hatch rate, while warmer temperatures will speed it up.

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This photo, taken several days after the egg was laid, clearly shows the ridges that run up and down the outside of the shell, distinguishing it from other insect eggs as well as milkweed sap.
Photo credit: Stephanie Rathsack

Three of our four eggs hatched on Friday, May 26th and the fourth is scheduled to hatch some time today.

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These two eggs side by side allow a clear distinction in age to be seen. The egg on the right is several days old, but is not yet ready to hatch, while the egg on the left has become translucent and allows the viewer to see the black head capsule of the caterpillar inside. This change in appearance indicates that the caterpillar could be emerging anywhere between hours and minutes.
Photo credit: Stephanie Rathsack

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Another view of the egg preparing to hatch.
Photo credit: Stephanie Rathsack
River Bend’s last monarch egg shows signs of being ready to hatch today, and we are eagerly waiting for it to emerge. Meanwhile, the other three caterpillars have already completed their first meal (their own eggshells) and have moved on to feeding on the provided milkweed leaves. As a species, monarch larva feed EXCLUSIVELY on plants in the milkweed family. Pictured here is the plant “common milkweed” which can often be found growing along roadsides and in prairies.

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When monarchs first hatch, they are roughly the size of the egg they were in, and their coloration is vastly different than their older counterparts. While older larva will have the distinct black, yellow, and white banding, these younger caterpillars are light gray with minimal banding, and have a large, black head.
Photo credit: Stephanie Rathsack

After feeding on its eggshell, monarch caterpillars will immediately begin to feed on the milkweed plant they were laid on. These youngest larva are known as “1st instars”, indicating that they have not yet molted their skin. After feeding almost nonstop, they’ll be ready to molt in several days. River Bend’s caterpillars are all currently 1st instars.

7 circleFirst instar caterpillars will feed in a circle around themselves until they’re large enough to not be at risk of drowning in milkweed sap.
Photo credit: Stephanie Rathsack

As our caterpillars start eating for the first time, they feed in a very distinctive circular pattern. Many scientists believe that this is to decrease sap flow in the leaf. While the sap is toxic to almost every other animal species except the monarch, these tiny caterpillars could easily drown if sap were to start flowing out of the cuts they make as they feed. To prevent this, the caterpillars feed shallowly, and create a safe “island” for themselves.

Want to learn more?

Stop by our interpretive center any day during the week to talk to a naturalist and see the monarchs for yourself! The building hours are as follows:
Mon-Fri 8:00-4:30
Sat 9:00-4:30
Sun 9:00-2:00

Interested in getting more involved?

River Bend will be offering MLMP trainings to teach interested members of the community to become certified MLMP volunteers! Monitor at home or at River Bend, and help save this amazing insect from extinction.
Register online to attend the training scheduled for June 10th from 1:00-4:00pm.

For more information, see our website at: http://www.rbnc.org/

Taxidermy

Taxidermy: Tools & Techniques

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Last Saturday, about a dozen people filed into River Bend Nature Center to learn an ancient art—taxidermy.
Photo credit: Stephanie Rathsack

For centuries, people have developed ways in which to preserve animals: however, whether you’re doing taxidermy  to learn a new skill, to show off a trophy, or record scientific data, specific steps must be taken in order for the specimen to remain in life-like condition. This blog post is dedicated to outlining several common techniques used both in the past and the present to preserve animals.

Taxidermy may be performed on all vertebrate species, including all mammals, birds, fish, reptiles, and amphibians. And though the steps taken to preserve these different species varies slightly, the tools required are all fairly similar, and depending on your skill level and the purpose of the mount, can be quite easy to procure. Any project will require at the very least, the following items:

  • Protective Equipment (Gloves, safety glasses, etc), if done correctly taxidermy is fairly clean, but steps should still be taken to keep yourself safe
  • Sharp scissors or scalpel
  • Medical probe
  • Pins
  • Cardboard or foam
  • Buckets/plastic containers
  • A drying agent such as borax or cornmeal OR a tanning agent
  • Needle & thread

These are the basic supplies that will be required for almost any type of mount you are attempting, but as different animals and different techniques will vary, so will the materials required. As you gain experience, you may also find that you prefer specific brands, or specific tools over others.

Taxidermy is a mix of science and art that has been developed since the mid-1700s, and possibly even earlier. And though the number of methods and purposes are limited only by imagination, this blog post will cover those that are considered “tried and true” by taxidermy specialists, and are by far the most common.

  1. Mounted skin on manikin

This is the most common method of preserving a trophy animal and is what you’d expect for such projects as mounting deer heads, or creating life-size mounts of bears, cougars, and other large animals. In short, the animal must be skinned (the skin preserved by either drying or tanning) and then placed over a sculpted manikin of the specific species. These manikins are painstakingly created by wildlife experts in order to be as anatomically accurate as possible, but once created, they can then be mass produced. In the early years of taxidermy this would not have been possible, and even today there are some taxidermists who choose to sculpt their own models (in order to use the specific animal as a comparison) or create a model using the Victorian-era method of winding the body shape out of string as depicted in this image of William Hornaday.

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William Hornaday. the father of modern taxidermy, creating a lion mannequin by winding string around a wood base.

Once the skin is placed over the manikin, finishing touches must be made, such as repairing shrunken sections, restoring natural colors, placing eyes and teeth, etc.

But like any taxidermy method, the process will vary by specimen, the taxidermist’s skill, and materials available and a taxidermist may even use multiple methods on the same specimen to achieve the best results.

2. Preserving Skulls and Bones

Depending on the purpose for preserving the animal, the most interesting piece might actually be inside—ie, bones, skulls, and teeth. The methods for preserving these parts are in some ways much easier than attempting to preserve other softer parts (bone is far more forgiving than delicate skin, hair, or feathers), but care must still be taken to avoid damaging them. The first step in this method, is to skin the animal (the technique will vary depending on whether you would also like to preserve the skin in addition to the bones), and then to de-flesh it. There are many ways in which to clean the bones of flesh, including: burying in the soil, macerating in water, treatment with chemicals, exposing to flesh-eating insects/bacteria, boiling, or by hand. No one of these techniques will work one hundred percent of the time for every specimen, and often, best results come from using a combination of several. But regardless of the methods used, once the skull/bones have been cleaned of all flesh, they will need to be dried thoroughly before being whitened by letting it soak in hydrogen peroxide (never bleach!) and sprayed with a clear acrylic to protect the surface from dirt and oils.

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The steps of cleaning a skull as performed on a red fox skull. In this case, de-fleshing was performed with a combination of by-hand removal, and simmering in hot water.
Photo and taxidermy credit: Stephanie Rathsack

3. Tanning Pelts

One of the earliest methods of preserving an animal: In 19th century England, there was an increased demand for leather, which meant tanning (turning an animal’s skin into preserved leather) became commonplace. The methods for doing so have changed throughout the years (you won’t find many taxidermists relying on pig or horse brains to turn skins into leather anymore), but the practice is still variable, and depending on your experience and abilities, there are several different methods:

  • Tree Bark
  • Brain (both brain and bark are more natural, but very difficult),
  • Alcohol/turpentine
  • Salt/alum
  • Purchasing a ready-made tanning solution

By far, the easiest and most reliable method is purchasing a tanning solution, but taxidermists have had great success with all of the above methods and more. Basically, the tanning solution is meant to preserve the hide and prevent it from decomposing.

To prepare a hide for tanning, the animal must be skinned, either as a flat cape (think bear skin rug) or a tube (think hand-puppet), and all flesh/fat must be removed. The use of a sharp knife or de-flesher is a must, and great care must be taken to avoid puncturing the skin itself. It is also essential that the hide is de-fleshed quickly before bacteria have a chance to grow, especially if you intend to keep the fur on, rather than making leather.

Once all the flesh is removed, the hide has to be completely dried out. The easiest way to do this is to salt it by placing a generous layer of non-iodized salt over the flesh side of the hide, replacing frequently until all moisture has been drawn out. At this point, you would apply a lime solution to remove the hair if your goal is to make leather, but this step may be skipped otherwise. Afterwards, the hide must be ‘’thinned’, which means more scraping with the knife or de-flesher to make an even and easier to manage skin, removing all pieces that were missed the first time it was fleshed. Once the hide is thinned, it must be soaked in an acidic solution (pH of 2 or lower), then neutralized completely before the tan is applied. Depending on the method of tanning to be used, the process will vary, but generally the hide must be either soaked in the solution, or it must be brushed on in an even coating for several days. Once the hide is tanned, it is considered a stable hide and can be left indefinitely. But to finish the process, the hide must be ‘’broken’’, in which the fibers in the leather are pulled apart, leaving it soft and flexible. There are machines available for this process, but firmly stretching the hide or scraping it works well for small hides, and takes relatively little time. Once finished, the leather will have a lighter white appearance, and will remain pliable.

4. Study Skins

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This final method is almost entirely used by museums and collectors interested in preserving as much scientific data on the specimen as possible, while also saving space. Generally used for birds and small mammals, the specimens are worked into a round tube shape in order to more easily fit side by side in drawers, although they can be worked into other shapes as well.

In order to perform this technique, the animal must first be skinned, by creating a small vertical ventral incision and then carefully teasing the hide away. If done correctly, the casing containing the internal organs will remain in one piece and thus keep the entire process relatively clean. If the visceral mass is punctured, or bleeding occurs, you may use a drying agent such as borax to keep your work station clean as well as protect the skin from staining. Once the hide has been removed, it can either be pinned flat as a ‘’rug’’, or stuffed with medical cotton and sewed back together before being pinned into the desired shape. After the animal has been pinned, it must be left to dry for several weeks, up to several months depending on the size, though once dried it will remain fixed in this position.

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A participant in Saturday’s class works patiently to pose her mouse in just the right shape.
Photo credit: Stephanie Rathsack

Over centuries of improvement and experimentation, taxidermy is an art and a science that has truly come into its own. Where once even the most skilled taxidermist struggled to preserve small animals, today both experts and amateurs alike can create beautiful and long-lasting specimens. It is a rewarding process, whether you’re looking to save a trophy, or simply to acquire a new skill. If you do plan to try taxidermy on your own, it is important to keep in mind that many species are protected under law, and possession of any parts of those species is illegal, regardless of how they were collected.

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Patience pays off in taxidermy, as participants in Saturday’s class found out after their mice were completed in about three hours. 
Photo credit: Stephanie Rathsack

Interested in learning more or trying it out for yourself? River Bend Nature Center will potentially be offering more courses on taxidermy! Stay-tuned for announcements on our facebook page, website, and newsletter.

Taking Prescribed Fires off the “back burner” at River Bend Nature Center

Where there’s smoke, there’s fire. Or at least, that’s the idea.

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2017 shapes up to be a successful year for prescribed burns at River Bend Nature Center. This grassland/forest mix behind the interpretive center was one of the first locations burned this last Saturday.
Photo credit: Stephanie Rathsack

In a world where fire is often seen as a danger to life and property, it’s easy to forget that fire is actually a natural part of a healthy ecosystem, and that in some cases, it is necessary for the survival of native plants and animals. This leads many to ask how this could be possible, when the landscape after a fire looks as far from lively as you can get: shriveled and blackened grass, charred stumps, and an ashy sky. It doesn’t exactly look appealing. It takes a closer examination to discover the real benefit of allowing fire to move through our prairies and forests.

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Immediately following a fire, the ground is left dry and charred. But it won’t stay like this for long.
Photo credit: Stephanie Rathsack

Underneath the burned ground, an incredible change is taking place—nutrients that were once trapped inside plants on the surface are now recycled back into the soil. In this way, nutrients are not locked away, but become available for new plants to utilize. This becomes especially true in prairie ecosystems, where grasses are prevalent, dying back every winter and holding nutrients in their dead stalks above the soil line. Perhaps even more amazing after a fire, some seeds buried in the ground begin to stir and show signs of life after what could have been years of dormancy.

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Large, healthy trees remain undamaged when a prescribed burn moves past. The removal of competition around it will even help it to thrive.
Photo credit: Stephanie Rathsack

In some cases, seeds are even coated with flammable oils to encourage hotter fires. These fire-dependent species require high heat for germination to be triggered, when otherwise it would not occur at all. Plants developed such traits in order to exploit the lack of competition following a fire. With other species removed, new plants that germinate quickly afterwards do not have to fight for sunlight or water with any nearby neighbors. A famous example of this is the Lodgepole pine, whose cones are sealed with a special resin that melts away in the high heat of fire and releases the seeds. There are many ways that plants have evolved to make use of fire—species may rely on fire, smoke, or a combination of both in order to prosper.

1Source: http://www.austintexas.gov/rxfire

This knowledge flies in the face of years of misunderstanding—that ecosystems are always moving towards a state of equilibrium, where nature and all of its components end in harmony. The reality is far different—nature not only utilizes, but requires frequent “disturbances”, whether this be in the form of fire, flood, or landslide. And so rather than thinking of a forest or prairie as a linear progression towards an endpoint, it is better to think of them as a cycle, where plants grow, die, are recycled back into the system, and begin again. This mindset is known as ecological succession—old growth forests will inevitably become disturbed sites where new, younger individuals will emerge and age. In the end this results in a healthier ecosystem, which is easy to see when comparing pre-settlement forests to modern forests. Before human intervention, forests often had fewer but larger and healthier trees. Now, forests have far more trees, but they are overcrowded, smaller, and generally less healthy.

 

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Source: https://www.cs.hmc.edu/~sweil/bio52/3/fireeco.html

 

Ironically, it is the modern, “protected” forests that pose the greatest threat, both to humans and wildlife. When fire is prevented, forests mature beyond the point of being prosperous—food/water amounts and space lessen, and wildlife suffers as a result. Additionally, dead plant matter builds up, which creates more fuel. Eventually, the amount of fuel present in the forest may allow for a larger, hotter, and more dangerous fire to occur.

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Prescribed burns prevent fuel from building up in a forest or prairie ecosystem–the result is more frequent but smaller fires that are less likely to get out of control.
Photo credit: Stephanie Rathsack

And so it all comes down to word choice. Many of us may remember the famous Smoky the Bear phrase “only YOU can prevent forest fires”. This was a great and catchy slogan for a world where fire could cost hundreds of millions of dollars in damages, both to buildings and natural areas. But as we began to learn more about this land we were trying to “protect” by putting out every fire we could find, scientists began to realize that our “help” was actually causing harm. And so rather than advertising a negative image on “forest fires”, Smoky now reminds us to stop “wild fires” instead—that is, fires that are unintentional or out of control in a region where lives and property could be lost. This change of heart helped reduce the misconception that all fire is bad—and that any forest or prairie fire is a villain in an ecological sense.

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Nutrients are recycled back into the soil when dead vegetation is allowed to burn. Even greener patches along the river are able to be burned, as Emily Greger, Resource Manager, helps it along with a torch.
Photo credit: Stephanie Rathsack

But what does this have to do with River Bend? There is one more benefit from fire that River Bend will be utilizing very soon, and that is to use fire as a tool to remove invasive species. While hours of work every year go into removing invasive species from the property, pulling, cutting, and treating, it is not the most effective way to prevent the spread of non-natives. Fire works much faster and far more thoroughly than any “by hand” methods of removal, making it the most effective tool at our disposal. And while historically, prescribed fires have been used sporadically and on small sections of land, we plan to increase the area covered, and also begin burning on a regular rotation. One burn is not enough to bring a habitat back to “pristine” condition—it takes several burns in addition to other treatments, and the entire process might go on for years. However, in the end, after a lot of planning and work, the goal is that eventually we will be left with forests and prairies that resemble pre-settlement—healthy ecosystems filled with a large variety of native plants and animals.

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Visitors can expect to see signs of burning through the end of April, and sites on the list of potential burns are the rain garden, the large prairie by the Interpretive Center, ditches along Rustad Road, the gravel pit, and the prairie on Teepee Tonka.

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Tall grasses burn readily–moving very quickly across a prairie landscape. A “back burn” will prevent fire from spreading to undesired locations.
Photo credit: Stephanie Rathsack

Dates and times of burns are all weather dependent, and all burning will cease before May in order to protect ground nesting birds. Helping us with this process is the Faribault Fire Department, who has been donating their time and equipment for decades.

4357Fire creeps up to the banks of the Straight River which acts as a perfect fire break.
Photo credit: Stephanie Rathsack

And while we cannot ask for volunteers from the public to help with burns, there are several things you can do to help make this process as simple and safe as possible:

Take note of any and all signs posted notifying the public about potential burns. When burning, there will be a large sign posted by the park entrance asking that people stay away from the areas that are being burned, both for their safety as well as the safety of the staff—distractions can lead to dangerous situations. Another way that you can help is by attending several events that River Bend has coming up—the first is an OWLS (Older Wiser Livelier Seniors) presentation given by River Bend’s Resource Manager Emily Greger. The presentation will focus on invasive species, going beyond buckthorn and touching on lesser known species and methods for controlling them. Additionally, River Bend hosts Restoration work days where members of the public can come out and assist with a variety of restoration projects, including removal of invasive species. For more information on these programs and other opportunities please see our website: http://www.rbnc.org/

OWLS – https://riverbend.z2systems.com/np/clients/riverbend/event.jsp?event=1631&

Restoration Work Day – https://riverbend.z2systems.com/np/clients/riverbend/event.jsp?event=1641

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Fire will drastically change the appearance of a landscape, but in just a few weeks, this same location picture in both photos will be green with new and healthier growth.
Photo credit: Stephanie Rathsack

A Day at the River Bend Sugar Bush – part II

We last left off with sliding down snowy and icy paths to collect buckets of maple sap. It’s been a few weeks now, and the River Bend sugar bush is working at full steam. With a total of about fifty trees tapped, we are continuing to collect sap every day with the help of staff and volunteers. On March 6th we collected a record amount of sap for the season—145 gallons! (This was produced by the trees in less than twenty-four hours)

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Photo Credit: Stephanie Rathsack
In a record total for this year’s sap season, we collected 145 gallons of sap in less than twenty-four hours.

With that much sap alone we’d be able to produce about three and a half gallons of maple syrup. Our recent collection runs have been less icy, but far more muddy, making the treks through the sugar bush tricky at worst, and extremely messy at best.  But shoes full of muck is a fair price to pay for the increased sap production that occurs with days in the 40s and 50s.

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Photo Credit: Stephanie Rathsack
With warm weather, sap bags (which hold about 2 gallons) can fill up quick!

And though increasingly warmer temperatures hark the end of the sap season, we expect to continue being able to collect through the end of the week, and into the following week as well. Meanwhile, the maple sap that has been collected up to this point is getting boiled down to begin the transformation from sap to syrup. This process requires high heat over a long period of time, for which we use a maple sap evaporator, which looks a bit like a giant wood burning stove. The sap is fed into the tank via gravity, and heat from the fire evaporates the water out, slowly decreasing the liquid in the sap and increasing the concentration of sugar.

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Photo Credit: Stephanie Rathsack
We let gravity do most of the work, as the sap starts in a bin held high off the ground before traveling down into the boiling chambers.

Maple sap generally has a 2-3 percent concentration of sugar, and this must be increased to about 68 percent found in maple syrup. This immense reduction in water requires large amounts of sap to be boiled for several days before it is ready to be bottled as syrup. Again with the help of volunteers and staff, the evaporator gets up and running early in the morning, and requires constant supervision throughout the day in order to continue feeding the fire, monitoring sap levels, and preventing scorching.  Even after several days on the evaporator, the syrup still is not completely finished—it requires a period of time on a stove top where the heat can be more fine-tuned and the syrup can move through its final stages of processing.

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Photo Credit: Stephanie Rathsack
Sap is “finished” over a stovetop where temperatures and consistencies can be monitored more closely.

As the sap reaches higher and higher sugar concentrations, it must be watched closely until finally after filtering one last time, bottling can begin. For long-term storage of maple syrup, specialized jars are purchased in a variety of sizes. River Bend bottles their syrup in large gallon jars down to tiny half-pint jars and everything in between. These jars of “liquid gold” will make appearances in a variety of River Bend programs and activities.

 

Want to learn more about maple sap production/taste a sample of this year’s bounty? River Bend is offering a variety of opportunities for the public to get involved in the fun of maple syruping:

 

Maple Syrup Open House– Celebrate syrup season at River Bend Nature Center! On March 18th, 2017 from 10:00AM to NOON there will be a variety of fun and FREE activities to participate in. Learn about the maple syruping process with trivia and taste tests and visit the sugar bush to collect sap, and see the evaporator in full swing.

Maple Syrup Fun Run- scheduled for Saturday, May 6th, 2017. Our races include a 50K, 25K, 10K and 5K trail runs (all jumbo clock timed) and a one-mile fun walk on an accessible paved trail (untimed). Race entry fee includes entry to our Pancake Brunch after the Fun Run, and a race shirt.

Maple Syrup Pancake Brunch– Come out to River Bend on Saturday, May 6th for delicious pancakes topped with River Bend’s own real maple syrup. Our pancakes will be cooked by the expert staff from Bernie’s Grill! We’ll also have sausages, coffee, and juice to accompany our pancakes.