Sunday, November 17, 2013

Diamondback Watersnake

Diamondback Watersnakes (Nerodia rhombifer) are a large thick-bodied, defensive, often ill-tempered snake. They are common in NW Missouri and are found living in aquatic habitats right alongside Northern watersnakes (Nerodia sipedon). They get their common name from the diamond-like pattern that runs the entire length of the body. They range in color from light brown, gray or olive-yellow. There will be 30 to 65 black markings covering their body and the belly will be either yellow or cream color. They reach lengths up to 63 inches but average length is typically 36 to 43 inches. In Northwest Missouri this snake is common to abundant in areas where they occur such as Squaw Creek National Wildlife Refuge. I make frequent trips to this refuge and almost always see this species upon each visit. Late in the season, around August and September it is common to find the juveniles basking along the ten mile auto tour route.

(Juvenile Diamondback Watersnake)

Mating takes place in the spring, usually in April or May. Females will bask on logs and along the shore of waterways warming the young she carries inside. This species gives birth to live babies sometime in August or September. Average litter size will be approximately 36 neonates. Not all offspring will survive to adulthood. Most in fact will be picked off by predators which range from owls, hawks, herons, foxes, raccoons, cats, large bullfrogs, fish, turtles. 

Diamondback watersnakes eat mostly aquatic prey which includes fish, frogs, tadpoles, and possibly small turtles. Game species are not generally on the menu as they are too fast for the snake to capture, instead they feed on rough fish. However they will consume game fish if found injured or deceased. Carrion seems to make up a significant portion of their diet.This species is especially adept at eating bullhead and other catfish. Even with the spines that these fish possess it does not seem to deter the snake in the least. I have witnessed these snakes with catfish whiskers protruding from their throat. They seem able to recover from what would appear to be a life threatening situation without any ill affects at all. Special lateral areas located along the trunk or upper portion of the body are super sensitive to touch, much like the lateral-line system a shark uses. The slightest touch against these lateral areas will cause the snake to lash out in a rapid sideways motion in a strike response to possible prey. This creates an increase in their ability to capture prey as they cruise along shorelines. Often frogs will hop erratically when disturbed and instead of jumping out of dangers way will run headlong into the very thing it is trying to get away from. These snakes rarely miss a meal when it hops so willingly into their midst. 

(Diamondback watersnake trying to remain hidden from predators while scoping the area for possible food)

These snakes are often confused with Cottonmouths and needlessly killed. As far as I am concerned anytime humans are killing snakes it is a senseless and needless act. It is especially so for watersnakes. They do share the same watery environs as cottonmouths (A.K.A. water moccasins)  which contributes in part to the confusion. Watersnakes by nature are quick to defend themselves from possible threats. They will flatten their heads and bodies and are prone to strike. If handled they will spray copious amounts of musk mixed with fecal matter. This often "aggressive" behavior causes people to think that they are faced with a venomous snake. For some reason, and I can't figure out why, people associate aggression or defensive behavior in snakes with venom. 

In reality all too often venomous snakes are calm and well mannered whereas harmless watersnakes can give even the most experienced snake handler a run for their money. Another feature of watersnakes is a diamond or triangular shaped head. This is also associated with venomous snakes. While it is true that many venomous snakes possess heads that are diamond-shaped, so do many non-venomous snakes. This is not an accurate way to identify a venomous species. I've seen black rat snakes, under the right circumstances appear to have diamond-shaped heads. 

(Diamondback watersnake showing a very definite diamond or triangular shaped head)

These snakes will often pester fisherman by chasing their catch while it is still attached to the fishing pole. They will try to eat fish on stringers and many times I've heard reports of these snakes coming completely out of the water attached to the fish at the end of a pole. This can be a bit unsettling if you are the fisherman, especially if you have a distinct fear or dislike of snakes. This fear can be amplified if you mistakenly believe that you are being faced with a cottonmouth. Try to remain calm and cut your line releasing both the fish and the snake. Please try to refrain from killing the snake. Remember the snake is only trying to survive and your fish on the line appears to be struggling prey and is easy pickings for a hungry snake. Keep in mind snakes that exhibit this type of behavior are watersnakes NOT cottonmouths. I've never heard of cottonmouths behaving in this manner. Watersnakes deserve a chance to live as an important component in the ecosystems where they occur. They are vital to the food chain both as prey and predator. They keep aquatic habitats healthier by eating weakened fish and carrion. They control bullfrog populations which can over populate areas where they exist. This creates a whole separate ecological problem, especially if you are red-legged frogs out west.


These snakes often travel over land to find suitable habitats. When current conditions are no longer favorable or food sources run low they will move to other areas, often great distances to find suitable resources. They are commonly found in wetlands, marshes, temporary watering holes, ponds, lakes and small rivers. If the areas they are in dry up they will move to temporary wetlands, then when the rains begin again and their home range becomes habitable again they will return. During rainy seasons they will often hunt in wet grasslands. These snakes will travel to hibernation sites that may be shared by other species. They will also use crawfish burrows to hibernate in. During one of my trips to Squaw Creek I visited one of their wet prairies to look for Massasauga Rattlesnakes. I did not find any rattlesnakes but I did find a large diamondback watersnake basking near a crawfish burrow. I cautiously approached and the snake did not move. As I got closer I was surprised that this snake did not lunge at me or act ornery in any way. Then it became apparent why. This particular snake was dead. It did not have any visible wounds, burns or other apparent reason for its demise. 

 The image at left is the snake in question. I spoke to the wildlife biologist from the refuge and he felt that the snake probably died from exposure due to the recent burn they had done on the prairie. Maybe a type of smoke inhalation. Either that or it could have died from exposure to the cold night time temperatures. Often snakes begin coming out of hibernation in March and will stay near their hibernation sites. If they happen to wander too far out and cannot get back to shelter before freezing temperatures return they may perish.All of us living in the Midwest know how rapidly weather conditions can change here. In the spring we can go from 65 degrees to 35 degrees within a single day. Whatever caused this, it didn't fare well for the snake. Other potential issues are things like fungal infections or diseases. There is a fungus that is attacking snakes all across North America. It was first noticed in rattlesnakes, but has since been found in other species including watersnakes. Often these snakes exhibit white, powdery-like substances on their scales or will show signs of having eye problems. Still other times they show no outward signs of fungus at all. I found a diamondback watersnake on the road at the refuge that had a definite eye issue. I didn't immediately think of it as a fungal infection. I thought it was a series of bad sheds. Often snakes have trouble shedding and an accumulation of shed skins may be found on one or more eye. I photographed the snake and then later wondered if it could be a fungal issue. I submitted the photo to several experts and none could agree. Some said definite fungal infections and others said that it was a bad eye shed. So I have no definitive answer, but will post the image for your consideration.


While these snakes are prone to bite, the wounds are generally superficial. Although because of a special enzyme they possess in their saliva the bite may bleed profusely. Simply wash the wound and cover it with a bandage and you should have no ill affects. Unwashed wounds however can cause infections; keep in mind what snakes are eating. Dead animals, fish and other aquatic animals. 

One of my favorite things to do is to take children out and explore. We often find snakes and I encourage kids to watch and even sometimes catch snakes to get a closer look. We always return them where we find them, unless of course we find them on the road then we place them somewhere safe away from road traffic. Allowing children to explore in a safe manner and be allowed to touch and admire these creatures creates a life long love of nature. Remember these children are the future voice of the natural world.

 Instead of killing or maiming something we do not understand, lets refrain from what might be our natural response to the unknown and marvel at the diversity of the natural World and try to appreciate all the creatures that call it home.


Tuesday, October 29, 2013

Western Fox Snake

Missouri is home to more than 50 types of snakes and one of my favorites is the Western Fox Snake. They are not common in Missouri, they occur in a few isolated populations and one such population is at Squaw Creek National Wildlife Refuge. At the refuge their numbers seem to be secure if not abundant. I've found several specimens at various times of the year, usually basking or crossing the road. Although we did find one hanging out in a hemp plant on top of a creek bank. Dr. Mills was able to capture it and show it to his students. It behaved remarkably docile and allowed us to handle it without offering to bite. This is not true however of every fox snake you will encounter. I've found them to be rather nippy and irritable. I assume just like humans or other animals each individual will have their own unique temperament.
(Fox Snake hidden in a hemp plant)

(Dr. Mills showing his skill at capturing a wild snake without being bitten)

(Success)
 
(beautiful fox snake)

Western Fox Snakes like many other animals have gone through a name change. They were classified as Elaphe vulpina, now they are referred to as Pantherophis vulpina. They are closely related to rat snakes and corn snakes. As juvenile snakes they so closely resemble black rat snakes that I personally have a difficult time differentiating them.

(Western Fox Snake)
 
(Black Rat Snake)

As you can see by the above photos these snakes are very similar in appearance in the juvenile stage. It isn't until they reach the age of about 3 years that they begin taking on their adult color form.
 
 (Black Rat Snake adult (Pantheropis obsoletus)

While Western Fox Snakes are not especially common in Missouri, in much of their range they are considered abundant. In parts of Michigan, Wisconsin, Minnesota, South Dakota, Nebraska, Illinois, Iowa and Indiana these snakes are secure in their population. In Missouri however they are protected as a threatened species. Missouri wildlife law states that an individual can own up to 5 reptiles or amphibians as long as they are not game species, venomous or protected. Fox snakes would be illegal to possess.

Habitat for this species varies considerably, they may be found in woodlands, prairies, hay fields or pastures. Squaw Creek is predominantly a wetland, they seem to thrive there in the wet prairies. Like other rat snakes they are opportunistic feeders, and will consume small rabbits, rodents, and birds. Like many snakes their diet as juvenile will vary some from the adult diet. They may feed on lizards, frogs and salamanders in addition to the rodents their adult counterparts seem to favor. 


Soon after coming out of winter hibernation males will seek females and mating will occur. 
 
Approximately a month after mating the female will seek a suitable site for her eggs. She may choose an old stump or hollow log, or even man made mulch piles and other man made litter. The temperature and moisture within the nest needs to be ideal to prevent dessication. In 2 months small, foot long, babies will emerge from the nest. The clutch may contain from 4 to 30 eggs depending upon the age and health of the mother. These juvenile snakes are perfectly equipped for life on their own and will receive no maternal care. Not all baby snakes survive to adulthood, in fact less than 10% survive the onslaught of predators. When you are a baby snake, everything wants to eat you, including foxes, skunks, other snakes, owls, hawks, eagles, coyotes, raccoons, and large bullfrogs. We all recognize that snakes are predators, they help keep rodent populations in check as well as controlling other small animal populations. They are key components in the habitats where they occur both as predator and prey. 
 
 



Monday, September 9, 2013

American 5-Lined Skink

Lizards are not real common in NW Missouri where I live. In fact we are pretty much limited to a few skinks and a racerunner. Typically the species that we see most frequently are the 5-lined skinks (Plestiodon fasciatus). They are commonly found under rocks, leaf litter, log piles or other refuges that make hiding easy. If water is nearby so much the better. In years of extreme drought like we've experienced the last couple of years they are much harder to find. While sweeping the porch off the other day a juvenile 5-lined skink darted out from under the welcome mat and disappeared in a crack in the foundation of the house. This caused my husband who was standing nearby to jump back a few feet as it startled him.....which made me laugh. This tiny lizard, barely 4 inches in length caused a grown man a moments fright. His excuse was he didn't know what it was. I think he thought it was going to go up his pant leg, which I must admit would have made me howl in laughter had it happened.  All that was seen was a streak of blue as it vanished. As juvenile lizards they have a gorgeous bright blue tail and bright highly visible stripes. As they age these stripes fade as does the blue tail. 


These skinks are relatively small for lizards and may reach lengths up to 8.5 inches from the tip of their nose to the tip of their tail. Adult males are typically larger than females. Females usually retain some of the striped pattern from their juvenile stage, although it will be faded whereas males become almost uniform brown or olive-brown in color. Some individual males in certain populations may retain some visible stripes. The most distinctive feature of the male is his bright orange head during breeding season.


Mating takes place in early spring, usually in April. The female will lay eggs in May or June. She will choose a nesting site with appropriate moisture and seclusion. This will typically be inside rotting logs or under log piles or stones.  She will remain with the eggs, guarding them from potential predators.This increases the survival rate of her offspring, even though it may put her in some increased danger of predation. Several days after the eggs hatch she will leave the young and they will remain on their own armed with all the survival skills they need. Providing predators do not capture them they will live several years.


Males can be very aggressive when defending their territories. They will chase other males off or stand their ground and fight. It is not uncommon to see males with battle wounds from tangling with other more aggressive males. While males are intolerant of other males within their territory, they do tolerate females and juveniles and show no aggression towards them. I recently spotted a skink under a piece of tin at our farm. Its skin looked rather odd and I could not decide if it was injured, covered in fungus or trying to shed. I shared the photos with several experts and all agreed that it was shedding. Like snakes and other reptiles skinks will shed their skin. Shedding depends on how much they are eating and growing, as well as on whether or not they have incurred some sort of injury that damaged the skin.


5-Lined skinks range throughout eastern United States and are very common in Missouri. They require no special conservation status. In Canada they are classified as endangered and it is illegal to own one. In Missouri you can own one as a pet and they are relatively easy to care for, although somewhat secretive. They feed on a wide variety of insects and spiders. 

They are also preyed upon by a wide variety of predators, including skunks, snakes, raccoons, birds, turtles, shrews, domestic cats and many others. These small lizards are an important component in the food chain where they occur, whether as prey or predator.

(5-Lined skink feeding on daddy longlegs (harvestman))

These fast moving lizards are sometimes difficult to see, but with patience and perseverance you will be rewarded with being able watch one carrying out its daily habits. Whether it is stalking food, chasing off a potential threat or pursuing a female to mate with these lizards or interesting and fun to watch. While it is legal in Missouri to make a pet out of one of these lizards, try to refrain from taking one home and instead leave it be and enjoy the knowledge that they are intriguing and unique inhabitants to the ecosystem where they occur.

Sunday, July 7, 2013

Snake Fungal Disease: The White-Nose Syndrome for Reptiles? By: Matt Miller




This milk snake captured in New York shows signs of fungal and bacterial infections. Could this become a major risk to snake populations across the United States? Photo: D.E. Green, USGS National Wildlife Health Center
By Matt Miller, senior science writer

 While studying timber rattlesnake movement patterns and habitat use in Vermont, researchers made a surprising discovery: snakes covered in lesions, particularly around their faces.
Called snake fungal disease, it’s a disease showing up with increasing frequency in snakes around the eastern and midwestern United States. Conservationists fear it could pose a similar threat to snakes as white-nose syndrome in bats. That’s a scary comparison: white-nose syndrome was first documented in 2007 in New York and has since spread widely, killing millions of bats as far west as Oklahoma. It has recently been raging through caves in the Smoky Mountains and has been verified in Kentucky’s Mammoth Cave National Park. So far, despite many efforts at controlling the spread, the disease rages on. Could snakes face a similar menace?

Timber rattlesnakes don’t move as widely as bats, but they do share some habits. They too hibernate underground in communal dens—often with other snake species. During hibernation, immune systems are suppressed. This combination can create a fertile ground for fungal disease growth and spread.There has been a lot of money spent on white-nose syndrome, and a lot of educational outreach, but so far they’ve been unable to stop the spread in bats,” says Emily Boedecker, acting state director for The Nature Conservancy in Vermont. “Snakes are even less appreciated by the public than bats.  An emerging disease is a significant concern.” The research partnership between the Vermont Department of Fish and Wildlife, the Orianne Society and The Nature Conservancy captured snakes to monitor their movements through radio telemetry. But they also weighed and measured snakes, and assessed their health. That’s when researchers found snake fungal disease. It has never been documented in Vermont before, but now it was turning up on numerous snakes.

Snake fungal disease has been documented sporadically in the past, but it began showing up with increasing frequency beginning in 2006. While it has been known to cause mortality, the effects on snake populations is yet unknown – in large part due to the secretive nature of snakes.
“We have more questions than answers,” says Dr. Chris Jenkins, executive director of the Orianne Society. “We don’t know if it’s a big deal yet, but we need to look into it closely.”
Jenkins notes that the disease does not appear to be spreading like white-nose syndrome; it is appearing in different parts of the country at the same time. It’s possible that snake fungal disease is not new but is only now being recognized. “Maybe we just weren’t looking for it,” he says.
When they emerge from hibernation, timber rattlesnakes bask in the sun, which appears to help control the lesions.

Another possibility is that the disease has always been present, but now has been exacerbated by a change in environmental conditions, including climate change.
In Vermont, researchers found that the timber rattlesnake population had relatively low genetic diversity, not surprising given its isolation. “Low genetic diversity and a fungal disease is a combination I find very disconcerting,” says Doug Blodgett, a wildlife biologist for the Vermont Department of Fish and Wildlife.

 Biologist Doug Blodgett captures a timber rattlesnake in Vermont. While the research is aimed at tracking snake movements for conservation purposes, it also assesses snake health. Photo: Matt Miller/TNC

 
The problem with wildlife diseases – indeed, any threats to wildlife – is that they are not considered serious threats until it’s too late. It is difficult to predict what will be a minor issue and what will devastate millions of animals – as has turned out to be the case with white-nose syndrome, and fungal diseases impacting amphibians.

While snake fungal disease was not a focus of the Vermont research, it may be one of the most important findings. Hopefully this time conservationists can gather necessary information and develop strategies to stop the disease before it devastates snake populations.
“We know so little about this disease, but now we know it’s here and we can start addressing the issue,” says Blodgett. “We know we can’t ignore it. The past should teach us that.”




Matt Miller is a senior science writer for the Conservancy. He writes features and blogs about the conservation research being conducted by the Conservancy’s 550 scientists. Matt previously worked for nearly 11 years as director of communications for the Conservancy’s Idaho program. He has served on the national board of directors of the Outdoor Writers Association of America, and has published widely on conservation, nature and outdoor sports. He has held two Coda fellowships, assisting conservation programs in Colombia and Micronesia. An avid naturalist and outdoorsman, Matt has traveled the world in search of wildlife and stories.
- See more at: http://blog.nature.org/science/2013/06/11/snake-fungal-disease-the-white-nose-syndrome-for-reptiles/#sthash.jt9LtP7q.dpuf
 




Matt Miller is a senior science writer for the Conservancy. He writes features and blogs about the conservation research being conducted by the Conservancy’s 550 scientists. Matt previously worked for nearly 11 years as director of communications for the Conservancy’s Idaho program. He has served on the national board of directors of the Outdoor Writers Association of America, and has published widely on conservation, nature and outdoor sports. He has held two Coda fellowships, assisting conservation programs in Colombia and Micronesia. An avid naturalist and outdoorsman, Matt has traveled the world in search of wildlife and stories.
- See more at: http://blog.nature.org/science/2013/06/11/snake-fungal-disease-the-white-nose-syndrome-for-reptiles/#sthash.jt9LtP7q.dpuf



Matt Miller is a senior science writer for the Conservancy. He writes features and blogs about the conservation research being conducted by the Conservancy’s 550 scientists. Matt previously worked for nearly 11 years as director of communications for the Conservancy’s Idaho program. He has served on the national board of directors of the Outdoor Writers Association of America, and has published widely on conservation, nature and outdoor sports. He has held two Coda fellowships, assisting conservation programs in Colombia and Micronesia. An avid naturalist and outdoorsman, Matt has traveled the world in search of wildlife and stories.
- See more at: http://blog.nature.org/science/2013/06/11/snake-fungal-disease-the-white-nose-syndrome-for-reptiles/#sthash.jt9LtP7q.dpuf