Archive by Author | Christina Locke

Snapshot Wisconsin opens in 8 new counties

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We’re happy to announce that enrollment recently opened in eight new counties, bringing our county total to 26. Any individual or organization in these counties with access to 10 acres of land is encouraged to apply to host a trail camera. We are also continuing to accept applications from educators and tribal members/affiliates across the state. Check out our project web page and monthly newsletter for complete updates!

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Science update: Canids

We’ve gotten some great questions from volunteers on species distributions. One from early in the project was, “Do the ranges of gray fox and red fox overlap?” We couldn’t answer that at the time since there is no comprehensive tracking effort for gray fox in Wisconsin. Great news: we now have enough data from Snapshot Wisconsin photos that we can start shedding light on questions like this!

So far, we’ve had 6099 photo subjects classified as canids on Zooniverse from photos taken at 484 cameras. Of these, 5832 classifications from 465 cameras had enough agreement among users that we feel confident in these classifications, while 267 classifications from 19 cameras need review by experts before a final classification is determined.

Do we find different species of canid at the same camera site? Yes we do, but some combinations are more commonly found than others. The below graph shows that coyotes are the most commonly seen canid in Snapshot Wisconsin photos, and most cameras capturing canids have so far only captured coyotes. The most commonly seen multi-species mixes are coyote and fox. We’ve captured relatively few photos of wolves so far, but most cameras that have captured photos of wolves have also captured coyotes and/or fox. (Note that cameras in the elk areas are not included in this graph, since those cameras are more clustered than our other cameras and are not representative of the state.) Click on the graph to view a larger version.

canid_graph2

The below map shows the canid data summarized by county. Data from the elk areas are included here and seen in the three small, square polygons. Note that since we do not have cameras in all parts of the state, and since different cameras have been active for different amounts of time, a lack of sightings in an area does not mean that a species is absent there – just that we haven’t seen it on our cameras (yet)! For example, we know from other data sources that wolves occur in more northern counties than what we’ve found on Snapshot Wisconsin cameras so far.

canid_map

What we can say about these data so far:

    • Coyote, gray fox, and red fox are found across the state.
    • Photos of gray fox and red fox are sometimes captured on the same camera, and their ranges appear to have considerable overlap.
    • Wolves are very infrequently detected compared to the other canid species.

As always, as we continue to expand the Snapshot Wisconsin program, we’ll be able to fill in more of the spaces in the map!

Is this animal albino?

From time to time, we find photos of animals with white coats that don’t typically have white coats. Are these animals albino?

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Albinism is caused by a genetic mutation whereby cells called melanocytes are “switched off” and fail to produce the pigment melanin. Melanin colors hair, skin, feathers, scales and eyes. Albinism can occur in any animal that has melanocytes, including mammals, reptiles, amphibians, birds and fish. Albino individuals may appear pure white, or may just be lighter overall than non-albino individuals.

Albinism is a rare condition, and there are several more common explanations for light coloration in animals. One is leucism, a condition caused by recessive genes that restrict the creation and/or distribution of pigment-making cells throughout the body during early development. Leucistic individuals may have light coloration overall, or they may have a light patch or patches scattered across the body.

Since either condition can result in individuals that appear white or very light in color, how can the casual observer tell the difference? It’s helpful to look at the eyes. Eye pupils normally look black because pigments at the back of the eye absorb light. In albino individuals unable to produce melanin, however, eyes appear red because light is reflected off blood vessels in the retina rather than being absorbed by pigment. This is why albino individuals experience a heightened sensitivity to light, and often some degree of blindness.  Since the melanocytes that produce eye color are not affected by leucism, leucistic individuals typically have normal eye color.

So, is the deer in the photo above albino or leucistic? Based on the dark eyes, it’s more likely leucistic.

White deer (albino or not) are protected from hunting in certain places, including Wisconsin. Why? White deer are not a special “breed” or subspecies, but they do hold social significance. People love seeing them, and some believe that they are good luck or magical. Certain areas of the state are now known for their white deer, and we are likely to keep spotting them on Snapshot Wisconsin cameras from time to time.

 

More info on color variation in animals:

 

 

Welcome to Season 6!

Here at Snapshot Wisconsin Headquarters, we’re up to our ears in data and we’re scurrying around to compile, assess and analyze what we’ve got. We’ll be posting updates soon on what we’ve got so far (including some really cool maps!). In the meantime, new photos just keep on rolling in, and it’s time for more classifying!

A few new features for Season 6:

  • Fewer photos of common species! That means fewer deer, squirrels, turkeys, raccoons, and bunnies proportional to the total number of photos.
  • New retirement rules that will retire all photos (especially deer photos) more quickly
  • Streamlined interface. Instead of getting a screen showing your classifications, you’ll pop straight to the next photo after pressing “Done.”
  • By and large, we’ve corrected wrong dates and times on the photos. There are still a few (literally just a few) that will have a clearly wrong year (1934 or 2021), but there shouldn’t be any that say nighttime when it’s really day, or winter when it’s really summer.

Snapshot Wisconsin trail cameras currently collect about 1 million photos per month, and we’re planning to add a lot more cameras over the next few years! That’s A LOT of photos, and we can’t send them all to Zooniverse. Our trail camera hosts get the first look at the photos they collect, and they do an excellent job helping us identify photos that don’t need to go to Zooniverse. Starting this season, their efforts will allow 75% of the total photos to bypass Zooniverse, leaving just 25% – the cream of the crop.

We hope you enjoy the season with these changes in place! Thanks again for all you do.

The science behind eyeshine

Here in the northern hemisphere, the autumn days are getting shorter and shorter. It’s getting darker earlier in the day, and our eyes have to adjust to dim conditions.

Without the help of fire or electric lights, we humans are pretty bad at night vision. Unlike many other animals, our eyes lack a specialized reflective surface that aids sight at night and in low light environments (caves, under water, etc.). This surface, called a tapetum lucidum, located behind the retina, acts as a mirror to reflect light photons.

eye_diagram

Humans lack the tapetum lucidum located in between the retina and choroid in the eyes of many nocturnal animals (Source).

Light enters the eye and hits photo receptors in the retina. Some light, however, will miss the photo receptors and pass past the retina. The tapetum lucidum reflects that light and gives it a second chance to hit the photo receptors and illuminate the scene.

Some of this light is reflected back out of the eye, which is why some animals’ eyes appear to glow in nighttime trail camera photos.  All types of camera flash, even the low-glow infrared flash of the Snapshot Wisconsin cameras, can reflect off the tapetum lucidum and cause an animal’s eyes to light up. (This is not the same as the red-eye effect seen in photos of human eyes which is caused by light reflecting off the blood vessel-rich choroid behind the retina.)

There is variation in mineral content and structure of the tapetum lucidum, which causes eyeshine in different species – and even different breeds of dog – to look different. Eyeshine may appear white, blue, green, yellow, pink or red.  It’s too bad nighttime trail cam photos are in black and white and we can’t see these color differences!

Animals having a tapetum lucidum (not extensive):

  • deer
  • carnivores: canids and felids
  • grazing animals: sheep, goats, cattle, horses
  • ferrets
  • lemurs
  • marsupials
  • fruit bats
  • ray-finned fishes and cartilaginous fishes including sharks
  • owls and a few other nocturnal birds
  • crocodilians including alligators (bright red eyeshine – spooky!)

Animals lacking a tapetum lucidum (not extensive):

  • higher apes including humans
  • kangaroos
  • pigs
  • squirrels*

*I’ve read that squirrels don’t have a well developed tapetum,  but flying squirrel eyes certainly glow in our nighttime trail cam photos. Anyone who can shed some light on this mystery, please leave a note in the comments!

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Sources:

Science update: Fisher distribution

Our July #SuperSnap was all about fishers, and we’re just going to keep on rolling on the fisher train! This science update was inspired by recent comments on a photo of a fisher in central Wisconsin. The location of the photo might cause confusion if you base where fishers *should* be on the range map we have posted. The map shows fisher range extending to only the very northern part of the state:

FisherMap.jpg

Whereas we’ve seen fishers on Snapshot Wisconsin cameras in counties pretty far south:

Fisher.jpg

In the case of a species like fisher, which was reintroduced to Wisconsin in the 1950s and expanded its range quickly, static distribution maps go out of date quickly. This brings up a larger point about range maps being inaccurate because they are based on old, incomplete or faulty data. We provide range maps to give volunteers an indication of where they are more likely to find a certain species, but these maps are by no means perfect. The fact that we do not have very good statewide data on the distribution of most species is indeed a major reason for starting a project like Snapshot Wisconsin!

Note that the above map shows counties where we’ve seen Snapshot Wisconsin photos correctly classified as fisher. Many of the gray counties do not have any Snapshot Wisconsin cameras and so we do not have any photos there yet. This is not to say there are no fishers in the gray counties!

July #SuperSnap

This month’s #SuperSnap selection goes to this agile fisher nominated by @Snowdigger:

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Fishers (Martes pennanti) are medium sized mustelids with slinky-like bodies and dark fur. Despite the name, fishers seldom eat fish. Instead, their diets consist of small mammals, and are one of a handful of animals capable of preying on porcupines. Fishers were reintroduced to Wisconsin in the 1950s, and have done well in the state since then – so well, in fact, that Wisconsin fishers have been re-located for reintroduction efforts in other states.

#SuperSnap is a monthly blog feature and a way for us to share some of the best Snapshot Wisconsin photos! Hashtag your favorite photos for a chance to be featured in the next #SuperSnap blog post, and check out all the nominations by searching “#SuperSnap” in Talk.

New elk reintroduction

The following post is by a guest blogger, Joe Dittrich,  research scientist at the Wisconsin Department of Natural Resources. Joe was involved in the new elk reintroduction in the Flambeau River State Forest (Sawyer County) and shares the experience here. Thanks Joe!

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Snapshot Wisconsin opens in 6 new counties!

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We’re happy to announce that enrollment is now open in six new counties, bringing our county total to 18. Any individual or organization in these counties with access to 10 acres of land is encouraged to apply to host a trail camera. We are also continuing to accept applications from educators and tribal members/affiliates across the state. Check out our project web page and monthly newsletter for complete updates!

A (Fawn)tastic Start to Summer

The following post is by a guest blogger, Taylor Peltier,  research technician at the Wisconsin Department of Natural Resources. Taylor, a new member of the Snapshot team, recently spent a few weeks in the field assisting with fawn captures, and shares her experiences here. Thanks Taylor!

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