This week we have a guest writer, Andrew Hoffman, a Ph.D .student at Ohio State University. Andrew is part of the Peterman Lab, led by Dr. Bill Peterman. The Peterman lab is conducting research on timber rattlesnakes. We are excited to share their story with you.
And now a word from our guest…
Persecution and unregulated forest clearing resulted in the near-extirpation of Ohio’s timber rattlesnakes. Ironically, regulated timber harvests may be the very thing that kept them around. Timber rattlesnakes once occurred in suitable habitat throughout most of Ohio, but populations are now centered on only a handful of State and Federal Forestry lands. These properties are the largest remaining forested lands in the state, but they exist because of timber resource needs. The fate of the timber rattlesnake in Ohio is now intricately linked with forest management practices, a situation that is mirrored in many other states.
During 2016, we began capturing and implanting radio-transmitters into timber rattlesnakes in southeastern Ohio to study their movement patterns and habitat use in a landscape with a long history of varied management practices. We are now in our third field season with movement data collected for 35 snakes (currently tracking 27) and have learned quite a lot! Below, I’ve listed a few of our findings:
One of our largest males catches some sun on a fallen log
Denning Behavior – Timber rattlesnakes are known for congregating at large, communal overwintering dens in and around rocky outcrops and cliffs, but snakes at our site behave quite differently. The 27 snakes we are currently tracking use 18 different den sites, and many appear to den alone. Moreover, most of these dens are nondescript holes on forested slopes with variable aspects. We also rarely see snakes at our study site basking near their dens (even on remote, time-lapse cameras). Though this may mean overwintering habitat is not limiting in southern Ohio, it makes it difficult to predictively model and locate unknown dens. We are also interested in when spring emergence happens and how snakes use the landscape during April, as this is the time when foresters conduct prescribed burns.
A nondescript rattlesnake den at our study site on a forested slop
Snake Fungal Disease (SFD) – The emerging fungal pathogen Ophidiomyces ophidiicola is, at best, a stressor on many North American snake populations and, at worst, a real threat to many species, especially pit vipers. We confirmed the presence of this pathogen in 2017 and again in 2018. Of the eight snake mortalities we’ve observed, four tested positive for this pathogen prior to death. Though some of these snakes were not symptomatic and were presumably predated, we are confident that SFD played a role in the death of at least two snakes. Though SFD clearly is a stressor in our population, five SFD-positive snakes remain healthy and have not shown symptoms of the disease. One large SFD-positive male was healthy during 2016, emerged during 2017 with numerous lesions, and went on to seemingly fully recover from the disease by the fall after a year of reduced movements and repeatedly shedding. We will continue swabbing our study animals biannually for SFD and monitoring the movements and habitat use of affected snakes in hopes of better understanding the effects of this disease on timber rattlesnakes in the wild.
A female in our study displays the characteristic facial lesions of Snake Fungal Diseas
Habitat Use – The question at the core of our study is how do different forest management practices affect the way timber rattlesnakes use the landscape? This is a multi-faceted and complex question that requires data on important resources for the snakes (e.g. food and thermally suitable sites), movement and habitat use data, and landscape/habitat metrics for the property. Though much of this work is still under way, our preliminary analyses are beginning to paint a picture for us. The figure below is taken from one of our recent poster presentations and highlights the variability we see at our site. Most snakes appear to be using disturbed habitats (sites that were previously cut or burned) more often than expected given their availability, but some snakes appear to avoid disturbed sites. In the future, we plan to use more detailed GIS data and more extensive telemetry data to determine whether certain management regimes result in habitat that snakes use preferentially and to what degree sex, body condition, and time of year dictate patterns of habitat use.
Though we still have a long way to go to better understand how forest management is affecting rattlesnakes in Ohio (and beyond), we are encouraged by how robust our study population appears to be and that snakes use both heavily disturbed, young woods and relatively mature forests extensively. We also try to engage in as many outreach events as we can, including programs to help educate the general public, landowners, and forest managers about this remarkable species! If you want to follow the lives of the snakes we are tracking, check out our Twitter feed @TimberTweets.
An adult female catches some rays in the waning days of fall 2017
Before we begin, let's review a few things:
What should you do if you encounter a rattlesnake on a trail?
What should you do if you are bitten by a rattlesnake?
How should you protect your dog?
Now, we can move on...
What have we done so far this year?
Jefferson County Open Space (JCOS) is working to formalize more recreation opportunities on South Table Mountain. To assist JCOS, Adaptation will be surveying proposed trail routes and parking areas to better understand how rattlesnakes might also be using these areas. We also want to know how rattlesnakes use the mountain during active months and where they spend the winter. To facilitate this, we will collect and surgically implant transmitters in 25 snakes.
So far, we have collected 13 rattlesnakes and Dr. Kevin Fitzgerald, with Alameda East Veterinary Hospital, has surgically implanted radio transmitters into them. We will continue to collect rattlesnakes until we reach our goal of 25 and we have started tracking the first 13.
Above is a map of the first 13 rattlesnakes we found on South Table Mountain.
Above is Prairie rattlesnake #3 overlooking the city of Golden.
If it wasn’t for our awesome volunteers we would not have found so many in such a short time!
One of our volunteers searching for prairie rattlesnakes and enjoying a fantastic view!
Many of the rattlesnakes we have found have had a nice meal in their belly.
Chris, one of our volunteers, with a Central Plains milksnake that was found crossing the trail.
Here is Ryan with a large bullsnake that one of our wonderful volunteers found.
#9 was on the move one evening. We tracked him into the nice evening glow of the sun.
We will keep you updated as the season continues. If you happen to see us while we are on the mountain, stop by and say, “Hi.” We are always happy to talk with park visitors. Until next time, keep one earbud out, keep your dog on a leash, and enjoy the beauty of South Table Mountain.
Periodically, we will have guest bloggers, sharing stories and insight about all things rattlesnakes! Here is our first guest blogger of the season, Bryan Hughes, of Rattlesnake Solutions in Arizona, giving us some insight about urban rattlesnakes!
If you live in an area where rattlesnakes do, you may be like thousands of people across the country each day who have an unexpected encounter where you least expect it. While the bunnies and birds who are the intended target of baths and feeders are welcome sights, other wildlife will also show up, and this includes rattlesnakes. Even if your yard looks like the surface of Mars and wildlife doesn’t want any part of it, you can still get the occasional wandering rattlesnake show up for a bit of shade against the side of the house, or just passing through.
So what can you do to keep snakes out of your yard?
The first is the reduction of habitat. If you are offering food, water, shelter, or all three, you are inviting wildlife to use it. Get rid of any debris, remove leaf litter and keep landscaping tight, and only water what needs watering. If you’re on the fence about whether or not one of your bushes is pulling its aesthetic weight, get rid of it. If you’ve got an impenetrable jungle of rosemary that you’ve had on the list of stuff to take care of for months, get to it. The more places and spaces that offer shady refuge, the more animals can potentially use them. If not rattlesnakes themselves, their prey may be using them, and attracting rattlesnakes from well outside your property.
If you have a pest control guy that’s selling you snake-a-way or some other stinky stuff to keep snakes out: good news, you can stop the service and save some money each month. These snake repellent products do nothing to deter snakes; the only effect is a yard that smells like a cat box and a bottle of windex had a baby. How do I know? I have personally captured hundreds of rattlesnakes from inside a snake-a-way perimeter. My team here in Phoenix has seen no difference at all in the possibility of rattlesnake encounter at homes that area treated with snake repellents and those that have not.
The most effective method is to build a physical barrier. Rattlesnakes can climb to some extent, but are not able to go up straight and flat surfaces without supporting texture. If you have cinderblock walls or a fence around the property, you’re halfway there. What you really need is something called snake fencing, or a rattlesnake fence. A rattlesnake fence is a series of preventative barriers that are attached to existing structures that seal open areas to an area smaller than the smallest baby rattlesnake, or about ¼”.
What’s a rattlesnake fence, and what do I need to know about it?
It can me made of many materials, but we have found that steel is best. The rattlesnake fence techniques we have worked out here in the brutal Phoenix weather would work anywhere, but each region may differ based on soil type and other factors, like precipitation. In general, stay away from materials that aren’t going to hold up well to the sun and elements. Steel mesh and steel plating will do this the best.
The snake fence needs to be constructed in a way that leaves no area open. A rattlesnake fence goes around the entire property but leaves a 2” gap in one area makes the yard an effective snake trap. While it may seem like just blocking the area nearest to the open wilderness would deter snakes, it can in fact do the opposite. Snakes movements often follow the outer edges of surfaces, as do the rodents that they eat that the snakes may be following. We have many projects that we unfortunately have to turn down because the home owner wants to snake proof the whole yard but leave a gate unprotected. While we are happy to have the opportunity to have the business, ethically we know that we cannot create something that could make the situation even worse.
There is a lot to understanding the little things; the small situations where a gate doesn’t quite match up with the wall, or the back of a fence bends up in a way that prevents a straight line of mesh, etc.. This is where having a group of installers who actually work with rattlesnakes or have some expertise with rattlesnake behavior is a must. Being able to interpret a situation and predict how a rattlesnake may interact with a feature, coming from a place of knowledge and experience of how rattlesnakes actually behave and move, can make the difference. While there are some snake fence projects that are done by handymen and pest control companies, even DYI by the home owner, that rattlesnake experience is often what really separates the effective fences from the ones that we are called to catch one that slipped in. More than half of our rattlesnake fence projects are re-work of existing fence projects that failed to effectively stop rattlesnakes. This is a job that must be done correctly, or not at all in most cases.
Why is rattlesnake fencing important?
Even if you don’t have a home bordering a wild area where a rattlesnake on the patio is a possibility, rattlesnake fencing and the development of a workable standard is an important component to wildlife conservation. Relocation of rattlesnakes, when done properly, is a great way to resolve a rattlesnake situation. However, in order to be a long-term sustainable solution, action must also be taken to prevent future problems. Relocation followed up by rattlesnake fence installation is a newly developing recommendation for long-term success in areas where rattlesnakes and residential areas come into conflict.
Check out Rattlesnake Solutions for more information on rattlesnake fence and prevention services in Arizona and Adaptation Environmental Services snake fencing services in Colorado.
How much do I need to worry about rattlesnakes, really?
Rattlesnakes are certainly something to be cautious about in areas near wild, native habitat. However, even in places where rattlesnakes are very numerous, it’s something that can be managed with some thought and consideration of the big picture - a rattlesnake in the yard is a symptom of a larger problem of wildlife displacement, ongoing development, and ultimately unintentional provision of needed resources by homeowners. Just be mindful of the possibility, and you’ve already handled the hard part.
TLDR; get a rattlesnake fence. Snake repellent doesn’t work. Stop feeding the bunnies.
Bryan Hughes is the owner of Rattlesnake Solutions in Phoenix, Arizona, a business dedicated to the conservation and understanding of rattlesnakes in urban environments, and to the safety of residents who encounter them. More information at https://rattlesnakesolutions.com or on Facebook at https://facebook.com/snakeremoval
Adaptation Environmental Team: Bryon, Joe, Kelly, Norma and Ryan