Of Sequences and Spotted Turtles…   Leave a comment

All those Spotted turtle DNA samples we collected in the spring have now been processed in the Laboratory of Molecular Studies at the Royal Ontario Museum. This lab work was completed during the fall, and now it’s time to see what our results can tell us about Ontario’s Spotted turtle populations! The markers we use are called microsatellites, and here’s how it works:
“Microsatellites” are specific sections of DNA which don’t code for anything and contain repeating sections that are only a few nucleotides long. Nucleotides are the building blocks of DNA – the bits that make up the DNA sequence. DNA is made up of four different nucleotides called adenine, guanine, cytosine and thymine – abbreviated A, C, G and T. Because microsatellites contain these repeats, the DNA is not always accurately copied in these sections. Sometimes, a microsatellite which contains 6 repeats is miscopied so that the new DNA strand contains 5 or 7 repeats instead.
The reason this is useful information is that every turtle (or person) has 2 copies of each microsatellite, each of which may have a different number of repeats. These differently sized copies are called alleles. The alleles you (or a turtle) carry are inherited from your parents. For example, if your mother has an allele with 17 repeats and another allele with 10 repeats at a particular microsatellite, then you inherited either the copy with 17 repeats or the copy with 10 repeats. You also carry a copy of one of your father’s two alleles. Your kids will carry a copy of one of the two alleles you got from your parents, and so on.
You already know that the length of the alleles changes slowly over time as microsatellites are occasionally miscopied. This means that when two groups of turtles are separated, the genetic profiles of these different populations gradually start to drift apart as they begin to contain different alleles from one another. As a result, each population ends up with a unique genetic fingerprint or profile. This process can take many generations and turtle’s have very, very long generation times! However, our results are showing that the genetic profile of some Ontario Spotted turtle populations have already become significantly different from one another.
These results are exciting for several reasons. They will tell us about historic connections between populations because we can see which populations which are now fragmented and isolated from one another are the most similar. And they will allow us to take our next step and build an assignment test, which will allow us to assign confiscated, poached individuals back to their population of origin. This test is in the works… more to come soon!
– Christina Davy

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Posted January 24, 2012 by thinkingturtles in Uncategorized

Where are they now?   4 comments

                As we’re all painfully aware, we’re heading into Ontario’s coldest time of year. Although the cold came late this year, it has arrived with a vengeance and all across the province waterways are freezing over. Safely tucked into muddy lake floors or burrowed deep under grassy tussocks in fens and marshes, our turtles are hibernating. This may seem to be a relatively safe season for turtles. Predators may be less likely to find them while they are hidden in their hibernation sites, and as long as everything stays stable, they can just ride out the winter cold until it’s time to emerge in the spring. And there’s the catch – it’s only safe if conditions are stable!

                Overwintering turtles and other aquatic wildlife depend on a constant supply of oxygen in the water to make it through the winter, as well as the water they are in remaining unfrozen. Some species require less oxygen than others and can tolerate changes in oxygen levels, surviving even when conditions are almost anoxic (“anoxic” means there is no available oxygen). However, if the oxygen levels really plummet even these species are likely to run into trouble. And if water freezes solid around hibernating turtles or fish, ice crystals can form in their tissue rupturing cells and causing serious injury and even death.

                So choosing a good hibernation site means choosing somewhere where the water conditions won’t change too much over the course of the winter.

                How does this relate to turtle conservation? Well, one way in which we can help protect turtles and other aquatic wildlife over the winter is by protecting our cooling and frozen wetlands from major disturbances. If wetlands are modified over the fall or winter in such a way that water levels change, the wildlife hibernating in them can be seriously affected. In severe cases, for example where water levels are dropped suddenly after turtles and other animals have already entered hibernation, sudden changes in water levels can cause huge die-offs. When the water under the ice becomes anoxic this can lead to large-scale fish kills and other problems, and since anoxia happens more quickly when there is less water available to hold the remaining oxygen, anoxic conditions develop more quickly when water levels drop.

                So although we are (sadly!) in a fairly turtle-free time of year, you can still help to protect Ontario turtles by keeping an eye on your local wetlands and making sure that any big changes that have to be made to them get saved until the spring!

 

–Christina Davy

Posted January 3, 2012 by thinkingturtles in Uncategorized

Happy New Year!!   Leave a comment

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Posted January 3, 2012 by thinkingturtles in Uncategorized

Why Turtles Are Terrible Pets   1 comment

I adore turtles. The babies are cute, the adults are fierce. Snapping turtles in particular are a favourite because I think of them as living dinosaurs. But as much as I love snappers, I would never, ever, want a dinosaur for a pet. Here are a list of reasons that I have compiled about why turtles make terrible pets.

1. They Swim in Their own Poop! Turtles are dirty. They smell. A lot. And they carry salmonella; a nasty bacteria that can make you very sick. Every time you touch your pet turtle you have to scrub your hands afterwards. Because they are dirty creatures, they dirty their living space quickly. Cleaning turtle tanks and keeping a clean filter takes a lot of work! This brings me to my second reason…

2. They Live in a Teeny Tiny Tank! Personally, I don’t think it’s fair for our wild reptile friends to be kept in such closed quarters. As a hatchling, a 5 ft by 2 ft tank may sound OK but for an adult turtle, this is hardly a spacious area. And who has ever heard of taking your turtle for a walk? Plus, a leash would fall off every time your turtle stuck their head back in their shell!

(Photo: A. Leifso)

3. They Need Special Care! If your turtle gets sick, you can’t just take them to a regular old veterinarian to get fixed up. They need to go to a special veterinarian. (And when I say special I mean more expensive).

4. Commitment! Turtles can live for a REALLY long time. They have the potential to live for about 100 years! That means that your pet turtle will probably outlive your marriage, or, if you are Kim Kardashian, your pet turtle will probably outlive all your marriages.

5. Loyalty! Turtles are not the same as a cat or dog. They are not loyal to you. They don’t like you. They will never like you. They will never run for help if you fall down a well (because they don’t care about you). Don’t mistake their swimming up to you when you approach, because sadly, it doesn’t mean they are excited to see you. You are simply their source of food. You are a means to an end.

6. My final reason for why turtles make terrible pets is because they are not cuddly. If you want a loyal friend, get a dog. If you want a cuddly friend, how about a feline? Because while hatchlings are adorable, they will not warm your feet at night in bed.

— Ashley Leifso

Posted November 7, 2011 by thinkingturtles in Uncategorized

On a bizarre human impulse to move stuff around…   Leave a comment

I’ve given several talks to the public and to interested groups of people over the past few months about turtle conservation, and there’s a recurring theme that really interests, puzzles, frustrates and fascinates me. Here’s how it goes: I speak with a group of people about turtles. The group is usually interested before I even start. By the end, they’ve learned some things about turtles. They want to help. Afterwards, we chat and people share their stories of turtle encounters – and here’s the story that keeps coming up. It’s always a variation on this: “Once, we (my family, friends, uncle, etc). were driving along [some highway in Ontario somewhere] and we found [Painted, Snapping, Spotted, Blandings] turtle on the side of the road. So we took it home.”

OK – so firstly, what is it about us humans that makes this such a common response to meeting a turtle at the side of the road?

Then the story continues with something like this: “then it lived in [an aquarium/our bathtub/our swimming pool] for a while, and then we let it go.” The real theme here is that nearly all of these stories have ended with the turtle being released somewhere other than where it was originally found, usually because whoever took it couldn’t remember exactly where they found it, or it was too far away to be convenient.

Obviously this is not only illegal, but more importantly, it is not likely to work out well for the turtles involved. They end up in sub-standard captive conditions for a while (despite everyone’s best intentions, swimming pools are not a suitable habitat for a freshwater turtle) and then they get dumped somewhere they’ve probably never seen before, where their chances of survival are much lower than in their own home range. So it’s not a good situation. But although I’d like to come back to this problem later, it’s not actually the point of this post.

What I want to know is, why we do this? Why are we apparently programmed to move turtles around? I haven’t spoken to THAT many people, and even with a small sample size this story (with all its variations) just keeps coming up. For some reason, we not only tend to pick up turtles we find, we also move them around a lot. I wonder how many turtles get moved around Ontario each year?

— Christina Davy

Posted October 19, 2011 by thinkingturtles in Uncategorized

First Patrol   Leave a comment

Snapping turtles feasting on a Carp carcass. (Photo: A. Leifso)

One of my most memorable days of turtling this summer was the first day we went out to patrol Spiny Softshell nesting site for nesting turtles. We had started walking at 11AM and although it was a beautiful day, we didn’t find any Softshells. The only thing to note was a handful of large dead fish that was being washed up on shore. On our last sweep of the beach, the two of us on patrol stopped suddenly at the same time because we saw the same dark spot up ahead by 150 meters. We started creeping up, voicing our thoughts out loud that this dark blob was way too big for a turtle. It neither turned out to be a Softshell or a single turtle. The dark moving blob was 8 Snapping Turtles feasting on the same large dead carp we had found earlier. Snapping turtles love to eat freshly dead things (carrion) for dinner but I had never until that moment seen such a large group of them feasting together.

Snapping Turtles wait to be measured before being released. (Photo: A. Leifso)

We quickly dropped everything we were carrying and ran up to them but as we approached we realized we did not have a plan! The snappers started to scatter so we caught the ones starting to swim into the deeper water. Turtles may be slow on land but they are super fast in the water and can quickly escape me (a mediocre swimmer at best). Carrying them to land, we used nearby thin logs as a makeshift playpen, although they probably thought it was more like a prison. Back and forth we ran, catching turtles by the carp and putting them in the pen, catching turtles escaping from the pen, and building ever more of our make-do holding pen.

Swallowtail Butterflies feasting on dead fish. (Photo: A. Leifso)

Our method of processing became refined. One of us was on lookout, catching any escapees and all the while being the note-taker. The other person measured and notched the turtles, which was quite difficult in the sand. We eventually mounded the sand into a pile to place the turtle on. We did this because on their backs, snapping turtles will roll right-side-up almost immediatly by using their long necks to reach down to push their heads against the ground and flip over. Setting them on a bit of a pedestal made it a little more difficult for them. All in all, it took 3 hours to process the 8 turtles and…

…days later, we found out snapping turtles aren’t the only creatures to feast together on dead fish!

– Ashley Leifso

Posted September 23, 2011 by thinkingturtles in Uncategorized

Slowing down for the season…   Leave a comment

As the evenings get cooler and cooler, I find myself slowing down a little, getting into a more mellow groove and getting ready to pull out some big fuzzy sweaters and spend more time indoors to stay warm. Of course, our turtles are all getting ready for the cooler weather too! As the temperature drops, turtles across Ontario are moving towards their hibernation sites, spots which they know will be safe to use over the winter. What makes a perfect hibernation site for a turtle? Let’s just say it’s not what I’m looking for in the winter months! Turtles spend the whole winter under the water, often under ice. Because hibernating turtles don’t want to become scaly ice-cubes, they need to find sites which won’t freeze solidly to the bottom. They also need to get enough oxygen out of the chilly water to get them through the winter (since they won’t be able to come up to breath once the ice forms on top of their wetlands). Our turtles get through the winter by slowing down their metabolism (although they can still move if they need to) and exchanging oxygen across the lining of their cloaca – basically, they breath through their bums! In the case of Eastern Musk turtles (aka. Stinkpots), oxygen is also exchanged underwater across the surface of the tongue. However they get oxygen from the water, they need a site with water containing enough oxygen to get them through the long cold months ahead.

A Blandings Turtle basking on a grassy bank after emerging from a long, cold hibernation. (Photo: C. Davy)

Some turtles need more oxygen than others – recent studies show that Blandings turtles, for example, can tolerate winters in low-oxygen water which could not support some other species. But all overwintering animals need at least some oxygen to get them through. This is why changes in the water level of wetlands during the winter can be dangerous for overwintering wildlife. If a previously deep area (with lots of oxygen, and with lots of water under the ice) suddenly become shallow, for example, due to an ice jam or the bursting of a dam, turtles hibernating in that area may not have the temperatures or oxygen level they need to get through the winter. By the time things freeze over, it can be difficult for turtles to move to a different site. So the decisions they are making right now about where to spend the winter can literally be a matter of life and death!

– Christina Davy

Posted September 23, 2011 by thinkingturtles in Uncategorized