Graduation and where I go from here

I am pleased to announce that as of last Saturday I am a college graduate! It has been quite a while since I have written a blog and I haven't kept everything as up to date as I would have liked. So here is my best attempt to wrap up loose ends. 

My last semester at Ohio University has been quite the whirlwind as I am sure any 2020 graduate can attest. To get the low-notes out of the way, Covid-19 has kept even us wildlife students cooped up inside (more or less). It has been a bizarre and a far-from-painless transition to online learning, but we roll with the punches. The online lectures, coursework, and finals have pretty well blurred together and it's an incredible relief to be free of them (hopefully for good). 

Most of the time I would have dedicated to writing blogs this semester was consumed with writing my Senior Honor’s Thesis, which I recently completed and had accepted. I don’t recall how much I have talked about this project on the blog, so here is a little background information. I started work on what I have been proudly referring to as “Snakes on a Lane” late in my sophomore year. Together with the help of my advisors, Dr. Viorel Popescu and Dr. Carl Brune, I have analyzed a long-term data set of snake road mortality points to establish hotspots where snakes face an increased likelihood of being run over. With my manuscript completed, we hope to publish in a herpetological journal. 

Presenting my poster at the Ohio Willdlife Management Association Conference.

I have been hesitant to announce any of my future plans with the global pandemic throwing everything into uncertainty; but I am tentatively confident that almost everything is a go. A few months prior, I was accepted into the Ohio State University’s School of Environment and Natural Resources Graduate Program. I will be starting my master’s in Dr. Bill Peterman’s Lab working on the Ecology and Conservation of the Common Mudpuppy (Necturus maculosus), Ohio’s second largest salamander. I am beyond excited for this new experience. Finding the right grad school was a tedious, drawn-out process and I feel extremely lucky to have found this project and opportunity. I will be a fully funded student for three years (which means no TAing!) and will be conducting mark-recapture surveys for mudpuppies in hopes of better understanding their survivorship and demographics around Columbus. I will then be working in Northeastern Ohio to determine the potential effects of TFM (a lampricide used to kill the invasive sea lamprey) on mudpuppies. There is also the potential for environmental DNA work. I am extremely eager to start this new chapter in my academic career.

Last month, I was accepted to serve on the board of the Ohio Partners in Amphibian and Reptile Conservation (OHPARC). This is an amazing opportunity to learn about and partake in the herpetological work being done throughout Ohio. I feel very grateful to have been asked to join this group and look forward to contributing to the study of herps in the state.

My last big announcement is not 100% official with the inevitable hiring freeze associate with Covid-19, but I was recently hired to write for the ODNR’s Wild Ohio Magazine and other DNR publications. Hopefully once things return to some semblance of normalcy, I will begin to write natural history articles for the magazine (potentially accompanied by my photographs). 

The remainder of this blog is dedicated to all the people who made my success as an undergraduate possible. Without the help, encouragement, and camaraderie of those around me, I could not have hoped to be where I am today.

My endless thanks go to my advisor Dr. Viorel Popescu. I first met V (I was much too scared to call him that for about two years) as a freshman. He and Marcel Weigand hired me for my first official wildlife tech job that summer which stands as one of the best experiences I have ever had. Some time in my second year, Viorel suggested I work on an Honor's thesis with the added goal of getting an undergrad publication. He spent many long hours explaining coding and mapping to me and was alway enthusiastic and encouraging. He has been a phenomenal mentor and I really hope to work with him again in the future.

I must also make mention of the Popescu lab. This wacky, quirky group of graduate students and undergrads has been like a second family to me. I will never stop being inspired by their passion and dedication to wildlife and science.

I must specifically thank my fellow Box Turtle researcher team, Christine Hanson, Andrew Travers, Eva Garcia, and all the volunteers. You guys made those hot, humid, and tick infested months unforgettable. I start to get misty eyed just thinking of our adventures together, creating lists of the ridiculous made-up rules like "NO BREAKS," or the unexpected snakey finds hidden among the undergrowth. I'll miss Eva and my lab movie nights, or bickering with Christine because I took a wrong turn. I wish you all the best of luck with your future endeavors and hope we will get out in the field again one day soon. 

And of course, Marcel Weigand. It is hard to put into words the kind of person, mentor, and friend Marcel is. She is probably the most caring, compassionate, and fiercely loyal person I have ever met. I hope to emulate her endless love for the Box Turtles that we spent so much time following around in the woods in all my future studies. You have always been able to remind me of the humanity in everyone, even when it isn't easy. Your tenacity is an inspiration and I am constantly reminding myself how lucky I am to have you in my life. 

If I could one day be half the herpetologist Carl Brune is I'd be satisfied (and he is a physicist!). I cannot begin to thank Carl enough for all the knowledge he has imparted on me over the last few years of herping across southeastern Ohio. I can confidently say he has taught me everything I know about the reptiles and amphibians of my home state and beyond. Quarantine herping has made me miss our conversations about everything under the sun as we drive between hiking spots. I will always be grateful for your mentorship and friendship. And of course thank you for sharing your data with me and helping me to complete my Honor's Thesis. I can't wait to get back out in the field with you. How's Friday?

I must also thank Dr. Don Miles (DOMI) and Dr. Matt White for their wisdom, humor, and advice. I'll never hear the song American Woman without also hearing Miles' sing "American Bittern," or see a Cedar Waxwing without wondering why it's "the bird that rocks." As for Dr. White, "checking the lip" will be the first thing I do whenever I see a fish (regardless of whether its a creek chub or not). 

Thanks to Charlene Hopkins for bringing me out in the swampy backwoods to catch frogs, newts, salamanders, and to sex snapping turtles. Oh, and to peal roadkill off the asphalt. It might not sound like fun to some, but mornings at the wetland were my favorite part of the week. You taught me so much about the world of science and academia my freshman year and I will always be grateful to you for that. I hope your future is full of biting turtles and stinky ponds.

Thanks to Matt Kaunert for showing me my first Snot Otters. Getting out in the field with you was some of the most fun I have had. I really hope to join you in the streams again soon! I need me some Cougar Bob's and I can hear Tidioute calling my name.

So much thanks to Krissy Harman for always taking the time to answer my questions and teach me about careers in wildlife. My resume would be a shadow of itself without your help and insistence that I don't "sell myself short." I've had a great time getting out to do field work with you (though I won't miss the hard hats). Once quarantine is over we need to get back to our Thai Paradise gossip sessions.

Thanks to Holly Latteman. Sorry I didn't listen to your warnings not to catch snakes in South Carolina. You are one of the most encouraging and sweet people I have ever been lucky enough to know. Thanks for being our field mom in ornithology. You were a wonderful TA. Stay in touch! We gotta go Butt Birding soon!

I'm not crying, you're crying. Amanda Szinte, Kathleen Cook, Remington Burwell, Sam Kukor. You guys have been some of the best friends a guy could ask for. We struggled through classes, exams, and field trips together for the past four years. Without your friendship, college would be unrecognizable. You guys inspire me every day to follow my passions and be the best I can be. 

Kathleen and Amanda, I will never forget meeting you two at Darwin's birthday freshman year. Who would have guessed what all lay in store for us back then. We made it through some real hurdles together and I know I am the better for it because I was with you two. I cannot wait to hear where wildlife takes you. 

Rem and Amanda, I will alway cherish our strange "Rymandington" friendship which no one understood when we went to Ecuador. Can you believe that was two years ago now!?

Sam, I will dearly miss you forcing me to study at the library late at night before exams. I still have all our fish flashcards somewhere. I have obliterated CVA from my memory so I don't have anything to say about that. Remember when we waited till the last minute before Thanksgiving break to do our independent fish seining project? We had to identify 30 shiners by the light of our headlamps and that creepy motel behind the stream. I want a rematch in Drawful. I assume you want a rematch in Smash Bros since I am so amazing at it. Take care bud, I hope those plants and stuff take you far. 

Thank you to all my fellow OU Wildlife Club Officers, Maddy Sudnick, Sam Kukor, David Cole, and Kadie Omlor. You guys put in so much time and heart, even when it was thankless and a little unrewarding. I appreciate you guys so much. Thanks for making this club great!

And last, but of course not least, Julia Joos. I know you hate this kind of thing so I will try to keep it brief. Thank you for being the coolest partner in the world. I am in awe of your love for and knowledge of turtles. You are so endlessly encouraging, supportive, and understanding. I could have a conversation with you for hours and not even notice the time pass. I can't wait for our next adventure together. 

 

Oh, and special thanks to my parents, Nikki and Steve Wagner. You are the real reason any of this is possible. You have always done everything in your power to make my dreams come true. You can get excited about anything, make warm-hearted jokes in the toughest of times, and are always there to listen and be supportive. Thank you for everything.  

Also Coco and Pima for being very cute baby tortoises.

Thanks for reading
Hopefully many more adventures to come!
RBW

Expanding at a Snail’s Pace

The Magee Limpkin feeding on a snail in the genus Pluerocera.

In early July 2019, a juvenile Limpkin turned up outside of Akron, Ohio, superseding the species’s most northerly US record from Maryland in June of 1971 by nearly 250 miles. News of the state record spread throughout the birding community, and by nightfall, a binocular-clad crowd had gathered around the suburban pond where the young bird was calmly feeding on snails. Reports soon flooded in that this was no isolated incident, either. Just a few days earlier, another bird had been seen in Mentor, Ohio. One month later, a third Limpkin was reported from Magee Marsh, and in mid-October, a fourth from Mentor’s Veteran Memorial Park.

Range Map of the Limpkin in North America (Source).

The Limpkin (Aramus guarauna) is the only member of its genus Aramus. Cross the long legs and serpentine neck of a heron with the skulking gait and plump body of a rail and you will have something that quite resembles a Limpkin. These brown and white birds are inhabitants of southern swamps from Florida to Central and South America where they specialize on apple snails (Pomacea sp.) and other freshwater mollusks. With such a specialized diet, it’s a small miracle that the Limpkin has survived the draining and dredging of its wetland habitat.  Limpkin population trends are poorly understood, but the species appears to be stable in Florida. Recent declines in the northern portion of its range may represent a contracting distribution, and historical records suggest the Limpkin once inhabited Mississippi, Texas, and much of Georgia. 

Sightings of Limpkins north of Florida and extreme southern Georgia are rare, but records of vagrant Limpkins reaching northern latitudes date back to 1950s when an injured bird was found in Nova Scotia, Canada. Sightings of Limpkins in northern latitudes are typically one-offs and are short-lived. The Magee Limpkin on the other hand, has been seen on and off for nearly five months. 

Ohio isn’t the only state in 2019 to see its first Limpkin record. In August, Illinois’ first confirmed Limpkin was spotted on a lake near the city of Olney. In 2017, Louisiana had its first Limpkin record when a group of four appeared in December. The following month, a pair successfully reproduced for the first time in the state. This represents breeding nearly 350 miles west of the nearest confirmed breeding record. Two years earlier, Georgia had its first state breeding record near Albany. Decade long surveys suggest that vagrant Limpkins have been turning up with increasing regularity since the early 2000s. Alabama, Georgia, and South Carolina have seen the bulk of these vagrants, but Limpkins have found their way to Maryland, Virginia, North Carolina, Tennessee, Mississippi, and now Louisiana, Illinois, and Ohio.  

A bird turning up outside of its natural range is nothing special. Major weather events like hurricanes can blow birds off course, landing them in states where they have rarely or never been recorded before. In 2013, a Brown Pelican, a native of the Atlantic, Pacific, and Gulf coasts, awed birders when it spent the summer along Lake Erie after being swept up by a low pressure system. It represents only the third record of a Brown Pelican in the entire state.

For recently fledged birds, migration has a steep learning curve. Juvenile Scissor-tailed Flycatchers follow their parents as they use visual, magnetic, and celestial cues to navigate. These internal compasses allow them to travel from the prairies of central North America to the southern Caribbean and back each year. During these travels, juveniles can often become disoriented, landing them well outside the usual range for their species. Migration is not all learned either. Sometimes, a genetic mutation can cause a bird's internal navigation system to go haywire. This may partially explain why scissor-tailed flycatchers (as well as many migratory species) occasionally deviate from their set migratory trajectory and have been sighted across North America from Alaska to Nova Scotia. 

Then there are the dispersers, which Joseph Grinnell described as “the exceptional individuals that go farthest away from the metropolis of the species; they do not belong to the ordinary mob that surges against the barrier, but are among those individuals that cross through or over the barrier.” Dispersers travel farther than 90% of the population and are responsible for the rapid colonization of human-introduced species like the European Starling and House Finch. How else would birds that rarely travel farther than 50 km in a lifetime colonize eastern North America from one, small founding population in just a few decades? 

Due to its exploratory nature, dispersal is a highly risky endeavor, and many birds do not survive their forays into unknown territory. In 2018, a juvenile Great Black Hawk, a species native to central and South America, was found in Maine. It represents the first and only record of a Great Black Hawk in the US. Just why this bird traveled from the tropics to the northern forests is a mystery. The hawk was able to sustain itself on a diet of gray squirrels throughout the summer, but as winter encroached, the tropically-adapted bird suffered severe frostbite and later died in a rehabilitation center.  

When successful, dispersal acts as a positive feedback loop for population growth. Lucrative years of reproduction increase the odds some juveniles will be genetically predisposed to wander. Establishment of new populations by a few lucky dispersers bypasses the slow expanse of home range leapfrog that most individuals employ to avoid inbreeding. Newly colonized habitats are not subject to the same limiting resources that stall population growth, allowing a rapid expansion of the species across a wide geographic area. 

So what is responsible for Ohio’s sudden Limpkin mini-invasion? Limpkins are non-migratory birds, and the first sighting in early July and August precede the hurricane season. Following sightings have not been linked with any major storm events. A single Limpkin might indicate a faulty navigation system, but mutations are rare events and are unlikely to account for the multiple Limpkin arrivals in northern states. Juvenile birds dispersing from their natal territories seem the most likely explanation.  

Range of the native Florida Apple Snail (Pomacea paludosa). (Howells 2006).

Limpkins are closely tied to the distribution of their primary prey, the Florida Apple Snail (Pomacea paludosa). Florida Apple Snails are the only native apple snail in the continental United States and make up over 70% of the Limpkin’s diet. Extending from peninsular Florida to the panhandle to the southern edge of Georgia, the Florida Apple Snail matches the distribution of the Limpkin almost perfectly. Extensive wetland loss during the 20th century greatly reduced the density of native apple snails and contributed to Limpkin population declines and local extinctions. Today, the Florida Apple Snail is considered an indicator species for successful wetland restoration. 

A large invasive Island Apple Snail from Arthur R. Marshall Loxahatchee National Wildlife Refuge in Florida.

In the late 70s, several species of non-native apple snail, including the Island Apple Snail (Pomacea maculata), became established in the US. Due to this snail’s greater size and fecundity, it has been able to outcompete the native Florida Apple Snail and has spread from North Carolina to Texas and across much of the southeastern US. 

Range of introduced Island Apple Snail (Pomacea maculata formerly P. insularum). (Byers 2013).

Invasive apple snails are veracious consumers of aquatic vegetation and pose a serious threat to agriculture and native ecosystems. As they consume algae, these snails bioaccumulate toxins that make them a health hazard to both humans and wildlife. Snail neurotoxins have been linked to Avian Vacuolar Myelinopathy (AVM), a lethal neurologic disease found in waterbirds and raptors. Snails can also carry rat lungworm (Angiostrongylus cantonensis), a parasite that causes eosinophilic meningitis in humans.

The invasive P. maculata is a tropical species, and while it is currently limited to a handfull of southern states, climate change is poised to expedite its invasion. On average, ten new P. maculata populations are discovered each year. Many biologists feared that the replacement of the native Florida Apple Snail with its larger, tropical relative would spell doom for apple snail specialists like the Limpkin and the endangered Florida Snail Kite (Rostrhamus sociabilis). These larger snails are harder for juvenile Snail Kites to handle, reducing their ability to forage and, in extreme cases, leading to starvation.

Snail Kite from Loxahatchee. 

What is truly remarkable, however, is that these hardy invasive snails seem to be supplementing the declining native P. paludosa and have jump started Limpkin and Snail Kite population growth. Both species have been documented readily feeding on invasive snails, and the latter may even be adapting to this novel prey (Snail Kites are increasing in body size and bill length). The introduction of P. maculata into novel watersheds has been directly linked with Limpkin range expansion. Limpkins were once exceedingly rare in Lake Seminole, Georgia, but following an unprecedented increase in P. maculata, some twenty birds were recorded in 2017. The first Limpkins to breed in Georgia did so within 5 km of the first P. maculata colony to become established in the state. Nearly all vagrant Limpkins in Georgia, South Carolina, and Alabama have turned up in watersheds that have known populations of invasive apple snails. 

So there we have it; a growing population in the stronghold of their range has allowed Limpkins to disperse into new regions of the country. Even the small, imperiled population of Snail Kites seems to be following this trend. In October, the first record of a juvenile Snail Kite was reported from Presque Isle, Pennsylvania. But will these birds survive in the northern latitudes? Ohio has no native or invasive apple snails. While we do have our own introduced species of large snail, the Chinese Mystery Snail (Bellamya chinensis), our winters can drop well below freezing for months on end. Establishment of a new Limpkin population in the northern US is extremely unlikely. The best we can hope for at the moment is that our vagrant birds will leave for the winter, and if Limpkin populations continue to grow and expand in the southern US, Limpkins may become increasingly common Ohio vagrants.

Limpkin from Loxahatchee feeding on a mollusk. 

References

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