Author: nelson.794@osu.edu

Wintering strategies of our endangered animals

Over the past weeks we have seen that animals employ three strategies to survive our cold Northern hemisphere winters: migrate, hibernate or adapt. Many bird species migrate, amphibians and reptiles hibernate and mammals, in particular large ones, adapt. So today let’s look at how some  of the endangered or even extinct species survive(d) the winters in Ohio – only 5 more days to contribute to our campaign to purchase a new mobile cabinet for our endangered tetrapods, let’s keep them safe!

male Bachman's Warbler

male Bachman’s Warbler (Whatbird.com)

The Bachman’s Warbler, like most of today’s species in the family wood warblers, migrated south, in this case to Cuba. It is an example of how migratory birds face even more risks than their cousins who stay year-round in one place. Its populations probably declined dramatically as a result of habitat destruction both on the breeding and wintering grounds. The last confirmed breeding record of this species was in 1937, and it has not been reported since 1988.

 

Indiana bats in cave

Indiana bats cluster together and hibernate during winter in caves, occasionally in abandoned mines. For hibernation, they require cool, humid caves with stable temperatures, under 50° F but above freezing. Only a few caves within the range of the species (Eastern USA) have these conditions. To survive up to 6 months of hibernation they rely on their energy reserves in the form of fat. The stored fat is their only source of energy because insects are rare in the middle of winter. If bats are disturbed during hibernation and move around they use up more energy and may starve.

Hibernating Indiana bats in cave

Hibernating Indiana bats (Wikipedia)

The Allegheny woodrat is adapted to cold conditions: Its fur becomes slightly darker and longer and it caches food in small caves or rock crevices. They feed mainly on plant material which means that they need large piles of it as they eat about five percent of their weight daily. You can imagine that woodrats are busily preparing for the winter these days.

 

The Carolina Parakeet was rather unusual for a parrot species.

image_carolina_parakeet02First of all it was the only parrot species that ever occurred natively in the USA. Furthermore it did not migrate south in the winter but weathered the cold. This may explain why some of today’s introduced parrot species survive in the wild just fine. Did you know that the last two known parakeets, Lady Jane and Incas, lived together for thirty-two years in the Cincinnati Zoo, the same zoo the last Passenger Pigeon lived? Lady Jane died in 1917 and Incas, soon after, on February 21, 1918.

group of Eskimo Curlews

The Eskimo Curlew migrated to South America where it overwintered in wet pampas grasslands, intertidal and semi-desert areas. A long flight from the breeding grounds in the tundra of the Western Arctic.

The Passenger Pigeon established winter “roosting” sites in the forests in the southern US states, Arkansas to North Carolina south to the uplands of the Gulf Coast states. Birds timed their movements with the availability of food.

We hope this made you appreciate these species even more; please help us preserve their remains for future generations to study. Donate today!

How do mammals survive our cold winters?

Today we explore how mammals spend the winter. Some of them migrate, though often not in response to the cold but rather to changes in rainfall, some hibernate, but many adapt to cooler temperatures. To keep warm, they grow thicker fur, they may collect and store extra food to eat it later and they find shelter in tree holes or burrows. Some may even huddle close together to benefit from each others body heat.

bank voles huddling underground

bank voles huddling underground

Some sixty species of mammals call Ohio home. The ones that you are probably most familiar with, because they are fairly large in size, active during the day and frequent your garden, are the Eastern gray squirrel and white-tailed deer. At dawn and dusk you may catch a glimpse of a racoon or an opossum. The latter two can be seen looking for food at times, while they sleep through periods of bad weather.

Eastern gray squirrel

Eastern gray squirrel study skin

If you have an acorn-producing oak tree in your garden you may have noticed squirrels foraging busily and collecting acorns that they store in safe places so they can retrieve them when the ground is frozen and covered with snow. Squirrels do not hibernate, they slow down their activity and may sleep for days when a snowstorm hits. They build nests out of twigs and leaves in the top of trees where they hide and stay warm.

Their close relative, the Eastern chipmunk, also does not hibernate. These little creatures are now busy collecting food that they scurry down into their newly dug burrows. They do not hibernate even though you may not see them until spring. They sleep in their burrows and wake up periodically to feed on their stores. On a warm winter day you may even be lucky to see one run across the snow.

The Eastern chipmunk has a close relative in Ohio, the thirteen-lined ground squirrel, also known as the striped gopher. It inhabits grasslands and prairies in North America and as these habitats are disappearing makes use of substitutes, such as cemeteries. They often are not welcome guests though due to their extensive digging habit in these and other open areas such as golf courses. Their burrows are important though as they hibernate in them. In fall, these little creatures put on a layer of fat and prepare to sleep through winter. They truly hibernate, i.e. their body temperature, heart rate, breathing and metabolic rate drop below normal levels. Thirteen-lined ground squirrels can spend up to 6 months of the year in hibernation!

Next week we will reveal how some of the species associated with our current fundraiser survive(d) the winter, so please check back to find out about the Bachman’s Warbler, Indiana Bat, Allegheny Woodrat, Carolina Parakeet, Eskimo Curlew, and Passenger Pigeon. If any of these species are dear to your heart, consider donating for their preservation!

Reptiles in winter

Last time we talked about how birds spend the winter, many of them leaving our state and moving south. But what do animals do that cannot fly or move long distances? How do lizards, snakes and turtles stay warm in the cooler temperatures? Birds are endothermic homeotherms, animals that keep a constant body temperature and maintain this temperature through metabolic processes. They face the problem of not finding enough food in winter to maintain their high body temperatures. When our fields are covered with snow, frost has turned the soil rock-hard and trees and bushes have lost all leaves and berries there is not much left for birds to feed on (unless they rely on you filling your bird feeder all winter and some of them do take that risk).

Rufous Hummingbird Selasphorus rufus at a feeder in Wayne County, Ohio on December 5th, 2015 (© Ed Wransky, ML21615071)

Rufous Hummingbird Selasphorus rufus at a feeder in Wayne County, Ohio on December 5th, 2015 © Ed Wransky, ML21615071

Reptiles face an even greater problem, they not only have to worry about food but also about their body temperature dropping drastically, maybe even below temperatures that allow normal metabolic processes. As ectothermic poikilotherms they gain heat from the environment and their body temperature changes with the surrounding temperature. You have probably seen lizards and snakes basking in the sun, particularly early on a cool morning in spring or fall. The last mornings were good examples with temperatures in the low forties but the sun quickly warming up the ground. These reptiles are also warming up and most of the time, when disturbed, are only slowly moving out of harm’s way. Their sensory cells and muscles are not working well at low temperatures.

Eastern garter snake Thamnophis sirtalis

An Eastern garter snake Thamnophis sirtalis basking in the sun

 

So how do cold-blooded animals survive winter’s cold which comes with reduced daylight hours and little sun – at least in Ohio? Let’s look at turtles, for example. Do you remember the big snapping turtle that spent the summer in your garden pond and fed on all living creatures that would come close?

The recent colder temperatures have slowed the turtle’s metabolism. This means that it needs less oxygen and food. Once the water temperature drops (not quite yet, as you may have seen fog over your pond in the early morning indicating that the pond water and immediate air are warmer than the surrounding cool air, and the water appears to steam), the turtle will look for a sheltered area of your pond and descend to the bottom of it. It will hibernate below the frost line where the water temperature stays constant and the turtle’s metabolism can adjust to a constant rate. (Snapping turtles are actually hardy creatures that have been reported to be active and moving around below the ice on frigid winter days).

Early morning fog over pond

Early morning fog (CC0 public domain)

The turtle slowly uses up its energy reserves and keeps breathing. To sustain the latter turtles have evolved to breath directly through their skin and retrieve oxygen from the water itself. Amphibians survive the same way.

How did we find out about this amazing behavior of hibernation in reptiles? Imagine you are a scientist observing turtles, you watch them in spring, summer and fall and then they suddenly disappear until they resurface in spring. Your first thought may be that they die in fall, maybe right after they had laid some eggs which somehow survive the winter and develop into new life in spring. But the animals that you observe in spring are not young ones. You collect a few and take them to your local natural history museum, where you find many more specimens in the collection and you can compare them with each other. It turns out they are indeed adults and must have survived the winter.

Turtles in glass jars stored in ethanol

Turtle specimens in ethanol

A quick search of our collection database reveals that of the 609 specimens of some 35 species in the turtle family Testudines only one specimen was found alive in February, a Mexican mud turtle Kinosternon integrum that Ted Cavender, then curator of fishes at OSU, collected  in a stream 20 miles west of El Naranjo along Highway 80 in San Luis Potosí county, Mexico on Sunday February 7th. The year was 1971. This was two days after the crew of Apollo 14 started exploring the moon, but probably more important for the turtle, it was a very warm February, with temperatures in the low eighties and even into the nineties in southern California (Wagner 1971 – Weather and Circulation of February 1971). Maybe the turtle was fooled into an early arrival of spring? If such warm weather continued over several weeks, maybe the water temperature rose, increasing the metabolism of the turtle which would use up its energy reserves much faster and would require it to resurface to replenish its reserves. Given the exact data on location and date with this specimen we could investigate further.  If the scenario I laid out above is true, this turtle may even give us a hint at what may happen to turtles across the USA should temperatures continue to rise due to recent climatic changes. I hope you can see how a museum specimen can be a treasure trove of information helping us to understand today’s fauna and in some cases may even help us predict changes into the future.

Mexican mud turtle Kinosternon integrum

Mexican mud turtle Kinosternon integrum

We are still in the middle of our campaign to raise funding for the purchase of a new cabinet for our not-so-lucky animals, species that went extinct because of over-hunting, habitat loss and other mainly human-caused changes in their environment. Please help us spread the word and donate today.

Cool fact: The oldest turtle specimen in our collection is a common musk turtle from Franklin Co, Ohio collected in June 1896.

How can museum collections help us understand bird migration?

Millions of birds migrate south every fall. You may have noticed some recent changes in your backyard bird community. Most of our summer residents have left by now, Tree Swallows and Eastern Bluebirds will be back next spring. Some birds will not succeed on their long journeys, because we have put up many obstacles for them to overcome, such as buildings with clear, shiny windows. Birds try to fly right through them. Thousands of volunteers like you pick up these window-killed birds and take them to their local natural history museum. We prepare them into specimen skins and preserve them for future research.

Window-killed birds collected in downtown Columbus in spring 2013

Window-killed birds collected in downtown Columbus in spring 2013

Over the years these specimens paint a picture of certain routes particular species take, the timing of their migration etc. We have learned that not all individuals of a species migrate at the same time, often young birds migrate later than adults, females differently from males.

To find out when to expect migrating birds in your area visit the Black Swamp Bird Observatory. We can learn so much from our museum bird skins and studies will help us make migration safer for today’s birds.

Sometimes birds get blown off track on their long journey and end up in an unusual location. With so many bird watchers today, these birds usually stir quite a bird watching frenzy. In the past some of them have ended up in our collection like this Magnificent Frigatebird that Milton Trautman collected in Morrow county, Ohio on October 2nd in 1967, almost 50 years ago.

Natural history museum across the country help with these efforts. Read about this student’s project “What can we learn from 30+ years of bird migration data?” at the Field Museum in Chicago.

Before you get involved you may want to read this testimony from volunteers at the Field Museum who collected and prepared many of the specimens for the above study.

Watch this video:

video

Species of September: American White Pelican

Anyone who has walked through or even glanced into the Tetrapod Collection will have surely seen the taxidermy mount of an American White Pelican standing in the corner of the room. It truly is a charismatic bird.

taxidermy mount of an American White Pelican

Taxidermy mount of an American White Pelican

The American White Pelican (Pelecanus erythrorhynchos) is one of the largest birds in North America with an average wingspan of 9 feet. That’s even more impressive than the Bald Eagle’s 6-7 foot wingspan. During the summer breeding months, American White Pelicans flock to the Northern Great Plains of the U.S. and the southern parts of Canada. After breeding season, they migrate across the U.S. to their wintering grounds in the Gulf of Mexico and along the Southern U.S./Mexican coastline. During migration, they may be seen resting and feeding right here in Ohio, in particular at some of the larger lakes in the state.

American White Pelican sightings close to Columbus

Sightings (as reported on ebird) of American White Pelicans close to Columbus within the last 10 years

Like all individuals of the eight living pelican species (two of which, the White and the Brown Pelican, occur in North America), the American White Pelican has the distinctive throat pouch that is used to scoop up fish while feeding. Due to their large size, American White Pelicans can’t dive from the air for fish like other fish-eating species such as the Belted Kingfisher; instead they swim on the water’s surface and dip their bills into the water to scoop up fish. The pelicans will then tip their heads to drain out the water and swallow only the fish. To find out more general facts about these birds, visit The Cornell Lab of Ornithology.

As if the pelican’s beak wasn’t peculiar enough, scientists now say it may be used to tell males and females apart. In many birds, distinguishing males and females is easy since males have colorful and extravagant plumage features. When a male and female of a species look different in some way, it is known as a sexual dimorphism. However, there are some species of birds, such as the American White Pelican, where males and females have very similar plumage making distinguishing the different males and females difficult. However, research done by Brian Dorr et. al (2005) shows that male American White Pelicans have significantly longer bills than females. The researchers measured the culmen, the area of a bird’s beak that stretches from where the beak’s base meets the feathers to the end, of 188 American White Pelican specimens that were collected in Mississippi and Louisiana. Dorr et al’s research shows that measuring culmen length can be used to determine the sex of American White Pelicans.

Measuring the beak length of an American White Pelican

Measuring the beak length of our American White Pelican

So, can we use this method to at least determine our pelican’s sex? I went to work with a metric ruler and measured the culmen to a length of 280 mm. According to the study, a culmen length of ≥310 mm indicates a male and ≤309 mm indicates a female. Thus our specimen is most likely a female.

This is a great example of how research on museum specimens can help with identifying individuals in the wild. In our case, it helped with adding a piece of information to an old, well-preserved specimen and making it more valuable to the scientific community.

 

 

 

 

References

“American White Pelican.” Identification, All About Birds. The Cornell Lab of Ornithology, n.d. Web. 26 Aug. 2015. http://www.allaboutbirds.org/guide/American_White_Pelican/id

Dorr B., King D.T., Harrel J.B., Gerard P., and Spalding M.G. 2005 The Use of Culmen Length to Determine Sex of the American White Pelican. The Waterbird Society 28, 102-106. BioOne. http://www.bioone.org/doi/full/10.1675/1524 4695(2005)28[102:TUOCLT]2.0.CO;2

Species of August: Timber Rattlesnake

by Raymond Gonzo

Part of the Tetrapod collection holds preserved reptiles, most of which represent native Ohio species along with several species from other parts of North America. To find a Species of the Month, I ventured down the aisles of shelves with jars of snakes, lizards, turtles, and tortoises. When I saw this Timber Rattlesnake, one of our collection’s most impressive reptilian specimens, I made my choice. I chose an animal that is feared, and misunderstood, by many.

Attaining an average length of about 3-4 feet, the Timber Rattlesnake (Crotalus horridus – a frightening name for an animal that rather avoids than seeks conflict) is a fairly large snake. Like most snakes, Timber Rattlesnakes are feared by a lot of people who don’t understand them well enough. It’s important to remember that snakes such as the Timber Rattlesnake don’t seek out conflict with humans, but rather try to avoid it. A part of the fear people have for snakes comes from common misconceptions, which these facts below will hopefully clear up.

Their range stretches throughout most of the temperate forests in the Eastern United States and Canada, however they can no longer be found in Maine and Ontario. Here in Ohio, they can really only be found at the southern end of the state. Timber Rattlesnakes will mate during the spring and fall with the females giving birth to anywhere from 4-14 young during the late summer. What’s interesting about rattlesnakes (Timbers included) is that they give birth to live young, which is very unusual for a reptile. Many reptiles, just like birds, usually lay eggs from which their young hatch after some incubation time. When the snakes feel threatened, Timber Rattlesnakes will rattle their iconic tails as a warning to potential predators that get too close. These snakes eat a wide assortment of small mammals and can sense their prey using special heat sensory organs that are located on their heads. These sensory organs are known as loreal pits and are a characteristic common to all members of the pit viper family, which includes rattlesnakes.

When Timber Rattlesnakes deliver a bite, deadly venom will be injected through the snake’s hollow fangs and into the victim. A common misconception is that snakes are poisonous; when in actuality they are venomous. Venomous organisms directly inject venom into the victim whereas poisonous organisms have a poisonous substance covering their body making them dangerous only when eaten or touched. Learn more general facts about Timber Rattlesnakes from an Ohio Certified Volunteer Naturalist.

Quite a bit of research has been done on these snakes, a few years ago Rokyta et al (2013) reported that components of their venom seem to have changed. Some species of snakes (Timber Rattlesnake included) have undergone a dramatic shift in the lethality, and composition of the venoms they produce. Traditionally, Timer Rattlesnakes produced a hemorrhagic type of venom, which causes the snake’s victims to bleed to death from the inside out (visit the Snakes and Spiders web site for a full description of how snake venom works). However, this study shows that, at the southern end of their range, Timber Rattlesnakes are beginning to develop a bite consisting of neurotoxin venom. Neurotoxins attack the victim’s central nervous system resulting in cardiac arrest and trouble breathing thus making it much deadlier than hemorrhagic toxins. Similar research on the evolution of snake venoms is being done at the molecular level by researchers in the Gibbs lab here at OSU.

Timber Rattlesnakes are amazing animals that encompass both beauty and lethality. Their status as a top predator has even landed them a place in history as the species of snake that appears on the “Don’t Tread on Me” flag. While these are highly venomous creatures, it’s important to remember that they just want to be left alone and do their best to avoid conflict with humans. Should a Timber Rattle snake bite you or someone you are with then please follow the procedures outlined by the Wild Backpacker to ensure a safe and speedy recovery from any venom related injuries. If you ever encounter a Timber Rattlesnake NEVER try to approach or pick it up, instead leave it alone and in turn it will leave you alone. Timber Rattlesnakes remind us that sometimes it best to admire natural beauty from a distance.

References

“Snake Bite First Aid and Treatment.” Wild Backpacker – Survival articles
http://www.wildbackpacker.com/wilderness-survival/articles/treating-a-snake-bite

Rokyta D.R., Wray K.P., and Margres M.J. 2013 The Genesis of an Exceptionally Lethal Venom in the Timber Rattlesnake (Crotalus Horridus) Revealed through Comparative Venom-gland Transcriptomics. BMC Genomics 14, 394. BioMed Central. http://www.biomedcentral.com/1471-2164/14/394/

“Understanding Snake Venom and How It Works.” Snakes and Spiders, 3 Nov 2009.
http://www.snakesandspiders.com/understanding-snake-venom-works/

Species of July: Indiana Bat

Three Indiana Bat skins from the Tetrapod Collection.

Indiana bats from the Tetrapod Division

by Raymond Gonzo

There’s nothing like being outdoors on a warm summer night. The sunset, the fireflies, a barbeque all make summer nights truly magical. However, there is an important part of the summer night that you won’t hear too many people reminiscing about, bats flying overhead. Bats though play an important role in making these summer nights so pleasant and memorable, they feast on mosquitoes and help keep their numbers in check.

Here in the Tetrapod collection, we have several species of bats that have been preserved and placed in a glass container with labels for each individual so that we can show them to visitors. While any of the species that we have would make for interesting conversation, I feel that it would be most interesting to discuss a species of bat that is both unique and important to the Midwest and Ohio, the Indiana Bat.

Weighing the same as approximately three pennies and with a wingspan just under one foot, the Indiana Bat (Myotis sodalis) is quite small . Despite being small, these bats can have a large impact: they are capable of eating half their body weight in insects per night and when you do the math, a bat can eat 3.75 g of mosquitoes which amounts to roughly 1,500 mosquitoes at 2.5 mg each. Thus bats are highly valuable in pest control. Like all bats, the Indiana Bat will hibernate during the winter when there are no insects to be found. These bats hibernate in very large clusters and, like their Latin name (sodalis, meaning companion) implies, are very social. When hibernating bats slow their metabolism, heart rate and breathing rate to extremely low levels to conserve energy. Given that they cannot refuel during the cold months, their energy reserves are finite and any unnecessary movement will cause them to burn more of their fat reserves than they can afford to lose. Thus during hibernation, bats absolutely cannot be disturbed. This will cause the bats to starve and die before the warmer weather with replenished food supplies returns. To find out more about the Indiana Bat in particular, you can visit the U.S. Fish and Wildlife Service’s website.

The Indiana bat, has been endangered since 1967. One of the reasons is disturbance during hibernation. There are a few different causes for disturbance of the bats’ hibernation, but the biggest threat nowadays may be white-nose syndrome.

The white-nose syndrome is a fungus that was introduced to North American caves by European spelunkers sometime in the early 2000’s. The fungus causes a white patch to grow on the bats’ nose, hence the name; this irritates the bat and may alter its behavior. Bats with this syndrome have been observed flying around in the middle of the winter, burning more fat than they normally would, which ultimately leads to death by starvation. This disease has already killed millions of bats across the U.S. and Canada and according to some researchers, it may continue to do so before we will see improvement.

According to a study conducted by Wayne E Thogmartin et al (2013) the population of the Indian Bat will be ravaged by white-nose syndrome over the next century. The study conducted was able to predict the rate at which bats will die off should conditions continue as they are, and they’ve found that the Indiana Bat will survive into the next half century, but at greatly reduced numbers. There is, however, the chance that the bats will develop immunity to the fungus, which could turn things around.

Bats of all species (the Indiana bat included) are dying due to the white-nose fungus’ rapid advancement. If we lose these bats, then we lose a very effective regulator of insect populations. The good news is that there are many ways you can help bats, starting in your own backyard in order to make it more inhabitable for bats. You can also support an organization that is working to save bats (e.g. the organization for bat conservation), and you can attend programs to learn more about bats.

At OSU Marne Titchenell, Wildlife Extension Program Specialist has studied bats and knows about their ecology and management. Marne and other naturalists periodically give talks on bat conservation at local metro parks. This weekend, join a Journey into Nature with Bats at Glacier Ridge Metro Park on Saturday July 25th at 8pm or take a bat walk at Blacklick Woods Metro Park on July 31st. Happy bat watching!

References

Thogmartin W.E., Carol A.S.R., Szymanski J.A., McKann P.C., Pruitt L., King R.A., Runge M.C., Russell R.E. 2013 White-nose Syndrome Is Likely to Extirpate the Endangered Indiana Bat over Large Parts of Its Range. Biological Conservation 160, 162-72. http://www.sciencedirect.com/science/article/pii/S0006320713000207

“Indiana Bat (Myotis Sodalis).” USFWS: Indiana Bat (Myotis Sodalis) Fact Sheet. U.S. Fish and Wildlife Service, 18 May 2015. http://www.fws.gov/midwest/endangered/mammals/inba/inbafctsht.html

“White-Nose Syndrome (WNS).” USGS National Wildlife Health Center –. U.S. Geological Survey, 13 Mar. 2015. http://www.nwhc.usgs.gov/disease_information/white-nose_syndrome/

Bruce, Heidi, and Shannan Stoll. “How to Save Bats in Your Own Backyard.” YES! Magazine. YES! Magazine, 17 July 2012. http://www.yesmagazine.org/issues/making-it-home/how-to-save-backyard-bats

Species of the Month: Cane Toad

Picture of Cane Toad

Adult Cane Toad

by Raymond Gonzo, OSU zoology major

The other day I was working in the Amphibian section of the Tetrapod collection, when I saw two toad specimens that really stood out to me. The toads were almost the size of a Coke can, which is bigger than the American toads that you may find in your backyard. Another interesting thing I noticed about these toads was the fact that one specimen was collected in Fortin de las Flores, Mexico, and the second specimen came from Australia. How is it that these two specimens were collected on different sides of the planet? On the jars they were labeled Rhinella marinus, which struck a cord with me. I had heard that name many times before, but I couldn’t remember from where. A quick check through the Tetrapod Collection’s curatorial database revealed that the amphibian in question was none other than the infamous Cane Toad.

The Passenger Pigeon that I wrote about last month was a species that declined in numbers and went extinct due to human activities. The cane toad, Rhinella marinus, is an example of the opposite effect, a species that proliferates with human help.

Until the 1930s, the cane beetle, an Australian native whose larvae feast on the leaves of sugar cane, did excessive damage to the sugar cane crop. In order to control the beetle population, the cane toad was released as a new predator. The idea being that this toad would feast on the beetles and thus protect the sugar cane crop. However, it did not work out as planned, the cane toad became a major pest in itself.

Instead of controlling the beetles, the toads began eating everything in sight, which allowed them to thrive and reproduce at an alarming rate. If that weren’t enough, the toads are highly poisonous and release a deadly toxin if a predator, who has not evolved defense strategies against cane toad toxin, should try to eat them. In the Americas, there are predators who can eat the toads and consequently keep their population in check. For example, there are many crocodilian reptiles, snakes, and various species of fish that are both immune to the toxins and can be found in the toads’ natural habitat. Many Australian predators of frogs and toads are unfamiliar with the toxins and cannot tolerate them, which means they will often die from eating a cane toad. This has given the toads a chance to drastically increase in numbers. Interesting fact, the cane toad is in the same family (Bufonidae) as the American toad, Anaxyrus americanus, an example of related species having a very different effect on their environment, especially when displaced.

However, as recent studies show, over time species may evolve the ability to either recognize and avoid cane toads or be able to tolerate their toxins. In 2004, Ben Phillips and Richard Shine demonstrated that some Australian snake populations that are at risk of death by the cane toad have adapted to living with the invaders. The authors of this study found that snakes increased in size in areas where they co-exist with cane toads. Small individuals face a much higher risk of fatal poisoning by toads, thus over time this species has been selected for large body size. More recent studies have shown that spiders and ants may also help keep cane toad numbers in check. If you are interested in finding out more read this article in the Australian Geographic. You can also read the study conducted by Phillips and Shine.

There are hundreds of instances where animals from one part of the world are introduced to another area, and often times there are disastrous consequences. A local example of this is the Emerald ash

borer. The ash borer is a native to China, but turned into an invasive pest of ash trees in North America. Here at the Ohio State University, much research is being done on the impact these beetles are having on the local Ohio ecology. More information on the control of this pest can be found here.

When it comes to trying to control nature, mankind has a pretty mixed track record of both successes and failures. Invasive species such as the Norway rat, the feral pig, and the ball python are all examples of how carelessness can lead to the destruction of an ecosystem. The Cane Toad is just one in a long line of destructive invasive species, and with the increased inter-continental travel of the modern world, it certainly won’t be the last.

 

References

Phillips, B. L., and Shine R. 2004 Adapting to an Invasive Species: Toxic Cane Toads Induce Morphological Change in Australian Snakes. PNAS 101, 17150-7151.

http://www.pnas.org/content/101/49/17150.full

 

Birding BioBlitz for Earth Day

Earth Day is coming up (April 22nd) when people worldwide engage in activities that benefit our natural environment and/or raise awareness of environmental issues. We will kick off the week around Earth Day with an early-morning (7-9 am) birding walk through the Olentangy River Wetland Research Park on Saturday April 18th. Our goal is to see and record as many bird species as possible, hence BioBlitz.

More eyes will spot more birds, so please come and join us and help us assess the bird diversity. This is the best time to watch for birds along the Olentangy rivers, as migrating birds follow the river as a landmark. All 37 species of colorful Wood warblers that occur annually in Ohio have been reported at the OSU wetlands. Will we be able to see them all?

Students bird watching

You may want to refresh your memory of what they look like with the detailed information provided in the ODNR bird booklets, accompanied by a CD of their songs.

Whether you are new to birdwatching or a veteran, come join us on Saturday, we will meet in front of the Heffner research and education building; parking is free! Please bring a field guide and binoculars if you have some!

If you have any questions about the event, please contact Angelika Nelson at nelson.794@osu.edu.

Blackburnian Warbler adopted!

Recently a Blackburnian Warbler was adopted as part of our Adopt-a-bird program.

Millions of birds across North America are killed every year by collisions with windows and other man-made structures. Migrating birds are particularly vulnerable on their long-distance journeys. Birds in your backyard may spend the winter in South America!  It is important to document the incidence of window kills, so that actions can be taken to prevent them.

Museum collections of bird skins are accessible to scientists all over the world and each specimen holds a wealth of information: sex, age, nutritional status etc. Modern technologies allow us to gain information about feeding habits and genetic relations. Thus specimens contribute significantly to our knowledge of biodiversity.

If you adopt a bird for a year, you will receive

  • Your name displayed with the bird skin in the Museum for one year
  • Photo and detailed life history description (including sounds) of the sponsored bird
  • Photo documentation of the process of preparing your bird for the museum

Follow the preparation process of the Blackburnian Warbler:

Blackburnian Warbler in freezer bag

Blackburnian Warbler in freezer bag

 

Measuring wing length

Measuring wing length

Shaping the body with cotton

Shaping the body with cotton

The final specimen

The final specimen will be added to the collection

This program is in collaboration with the Ohio Bird Conservation Initiative, a non-profit group that works with businesses and citizens to prevent collisions of birds with buildings.

For a complete list of currently available species e-mail the collection manager.