Turtles – the Earth’s Biodiversity Heroes

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Shawn Hill

Before we talk turtles, we need to understand what biodiversity is and why it is important for us:

Biodiversity refers to the variety of life that is found in an area, a region, or on the Earth as a whole. Biodiversity includes all living things from plants and animals, to fungi, and all the way down to tiny microorganisms! 

We live in ecosystems: Ecosystems are communities of organisms interacting with each other and their environment. Ecosystems contain many natural resources and diverse wildlife that provide humans with essential products and services. These products and services are irreplaceable and cannot be provided or recreated by humans. Some examples are: services of water filtration; pest control; nutrient and pollution filtration; pollinators that support the growth of foods; and even agents that spread seeds are found in nature. These processes and species ensure that biodiversity continues. In ecosystems we also find sources of food, medicines and even our building materials. Finally, from star-gazing, to recreational activities, our mental and spiritual health also benefits from nature. 

How do ecosystems operate? Ecosystems rely on a

cycle of nutrients that is driven by the amount or the level of biodiversity that exists within them. In fact, biodiversity is essential to how productive and resilient each ecosystem will be.

For example, how fertile the soil is in an area is determined by the amount of microbes and fungi found there, which is then determined by how rich and productive the plants are, and the plant life helps and is helped by all the birds, fish, turtles, and other animals found there, and so forth.  So it is all connected!  The health and variety of wildlife, the quality of our water, air, food and life really relies on the the diversity of all living nature interacting together. 

Everything is so connected that the loss of just one species can result in the collapse of a whole ecosystem. One way to look at- when we remove a plant, bug, animal from an area, it is like removing blocks from a Jenga tower. The tower may not collapse right away but it has become weaker and could collapse when another block (species of plant, bug, or animal) is removed. Today, we have removed too many blocks! We humans have changed so much of the world’s ecosystems. We have transformed the landscapes by removing or relocating species partially or sometimes entirely. “Shaving” so much of the earth’s surface clean, even in your own backyard, has changed many essential processes. Removing native plants and trees, hardening surfaces, installing artificial lights at night and spraying insecticides, have all reduced biodiversity on a global scale, and have even contributed to the increase of the overall surface temperature of the Earth. 

The results are huge losses of species that have depended on the natural processes and nutrient cycles within an ecosystem. The local losses may still be small, but they have become thousands across the world and in every landscape, putting the earth on the course to a sixth mass extinction. A mass extinction is defined as a loss of more than three-quarters of the Earth’s species in a relatively short time period. So life as we know it is at risk.  

Why turtles are our heroes

We can take small deliberate actions to change and restore biodiversity- and that’s exactly what many people are doing in their homes, yards, neighbourhoods and communities! And one very important way you can help biodiversity is by helping our wild turtles! 

Turtles are one-of-a-kind vertebrates that have incorporated a shell into their skeleton. A turtle’s shell is made up of a fused rib cage and spine which has remained relatively unchanged for nearly 200 million years! Turtles were likely here before all the dinosaurs, they certainly have outlived the dinosaurs and they survived five mass extinctions. 

Not only do turtles have a distinct skeleton and body shape, but they also have a very unique lifestyle. One very important characteristic is that turtles have aquatic AND terrestrial territories. Turtles have incredible navigation abilities, and using chemicals in their brain as well as the sun, they travel between many habitats and ecosystems following very specific routes. They always know exactly where they are going! It’s not only where turtles go that is important, but what they are doing there, carrying and delivering! 

Many turtles are scavengers and get their nutrients by eating dead things from the bottom of waterbodies, in addition to eating small living plants and animals. In the lakes, rivers, ponds and wetlands that they occupy, they are effectively the cleaning crew, removing sources of harmful bacteria. This “nutrient” cycling keeps all of the living things in those ecosystems, including us, healthy. Because turtles travel between both aquatic and terrestrial ecosystems they are a major source of energy transfer between the two. Turtles’ diets and unique digestive systems means that they carry and deliver the seeds, bacteria and nutrients from one habitat to another. They essentially leave the gift of restoration. Turtles help new plants grow and ecosystems thrive; they bring new seeds and the necessary plant fertilizers across wide expanses as they travel between ecosystems, through their droppings!

But turtles are not just any harbingers of biodiversity: Turtles, and vertebrates in general, retain a large proportion of nutrients, specifically nitrogen and phosphorus, in their bones. Nitrogen and phosphorus are essential nutrients needed by plants for their growth. Because turtles have such a long life span and grow slower and slower as they age, adult turtles no longer use these nutrients for bone growth; instead, they become stable sources of large supplies of essential nutrients. The extra nitrogen and phosphorus that they get from the environment then gets carried and dropped off as they travel through their territories! For the seeds they leave behind, and the other plants in that habitat, turtles leave a trail of healthy and enriched biodiversity wherever they go!  

Despite being on the planet for eons and surviving mass extinctions, turtles are now at risk of disappearing too. Mortality from cars on roads, misinformed persecution (dangerous, threat to fish populations, etc.), and removal of turtles from their natural territories and environment, are all threatening the future of our heroes. When any turtle species disappears from an ecosystem, a very large role, that cannot be filled by any other creature is left. Become a turtle guardian in your community! Watch out for them on roads, keep them in lakes, and spread the word. 

There are so many reasons to love turtles, and a healthy environment is just one of them, let’s try and keep these guys around for as long as possible! For more information on how to help, check out the Turtle Guardians website! www.turtleguardians.com

Written by Jaime Kearnan, Turtle Guardians staff

Should We Stay or Should We Go Now? A Painted Turtle Hatchling Dilemma

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“So guys…should we stay in or go out?” A Painted Turtle Hatchling Dilemma

Turtle species in Ontario lay their nests in the spring and eggs start to hatch at the end of summer into early fall. Small hatchling turtles are faced with many challenges once they leave the relative safety of their nests. First, there is the feat of actually breaking through the ‘nest plug’ of soil that overlays their nest cavity. This plug can be quite dry and crusted by the end of summer, making it difficult for small hatchlings to break through (Costanzo et al. 2008). Next, the hatchlings need to navigate to nearby water and somehow avoid being eaten by a hungry predator like a migratory bird who is stocking up on fuel before their long journey south, or a Mink who can catch them on land or in water.

The hatchlings that make it to water safely, then have to avoid aquatic predators such as Bass or Muskie, then need to find enough food to offset the energetic costs of leaving the nest, and to fuel themselves for winter hibernation. Their last challenge before winter sets in is then to find a hibernacula; a safe spot underwater where they can hibernate all winter. Therefore, the risk of being eaten or not getting enough to eat are both very high for new hatchling turtles that leave their nests in the fall.

What if turtle hatchlings just stayed in their nest? Would they be able to survive until spring and therefore avoid all the trouble of emerging later in the summer when all the predators are most active and food sources are decreasing? By overwintering in their nests and emerging in the spring, food sources would be on the rise instead of on the decline (Costanzo et al. 2008). Some of Ontario’s turtle specie’s hatchlings are in fact able to overwinter in their nests! (Although no species uses this strategy exclusively).  Painted Turtles are the Ontario turtles that will most commonly overwinter in their nest, but hatchlings of Northern Map Turtles, Blanding's Turtles, and Snapping Turtles (in decreasing order) are also known to occasionally overwinter in their nests (Riley et al. 2014, Nagle et al. 2004, Paterson et al. 2011, Obbard and Brooks 1981).

To explain this “overwintering strategy” of remaining in their nests, let's explore the following questions about the Painted Turtle, Chrysemys picta.

Do Painted Turtle hatchlings always spend their winters in the nest?

No they do not! Painted Turtle hatchlings can emerge in the fall or overwinter in the nest and emerge the next spring. Scientists believe that hatchlings can sense environmental cues when in their nest cavities, and these may dictate whether they emerge in fall or spring. However, even within the same area these cues can be different for individual nests because each nest is slightly different in aspect (slope), moisture etc., and so some nests even within close proximity to one another might use different strategies. Also, even in the same nest, there are differences in moisture and substrates. Therefore there have been some reports of hatchlings within the same nest using different strategies, meaning some will emerge and some will stay to overwinter (Carroll and Ultsch 2007).

 Is it more common for hatchlings to emerge in fall or spring?

 Patterns change from year to year, but in general the trend is that the majority of Painted Turtle hatchlings overwinter in the nest and emerge the following spring, (Lovich et al. 2014, Riley et al. 2014). For example, in Algonquin Provincial Park, Painted Turtle nests were monitored and in the cohort of 2010-2011, only 2 nests emerged in the fall, while 23 overwintered in the nest and emerged in the spring. However, in the following year 16 nests emerged in the fall and 20 overwintered and emerged in the spring (Riley et al. 2014).

What are the benefits of staying in the nest? What are the risks?

Benefits: avoiding emergence in the fall at a time of peak predator abundance and decreasing food sources; more time for small hatchlings to develop within the relative safety of the nest because predation of nests decreases with time; avoiding a year of hibernation and related risks of low oxygen and slowed metabolisms while they are small; and being able to emerge in the spring when food sources will be increasing and there are less predators too!

Risks: exposure to below freezing temperatures within the nest cavity and potential death due to cold temperatures, running out of energy stores and dying from energy depletion before spring, and drowning from nest flooding.

What factors influence whether hatchlings emerge in fall or spring?

These factors are not completely understood, but it seems that there are multiple factors at play. Presence of sarcophagid fly larvae which feed on turtle eggs and hatchlings is often associated with fall emergence as the flies will otherwise disturb the hatchlings. Also a nest on a steep slope facing towards water, especially southward slopes facing the sun, or nests in bare ground with less vegetation cover and therefore less shade seem to create circumstances for hatchings to emerge in the fall. This is perhaps because these situations increase nest temperatures which may encourage hatchlings to venture out of their nests in the fall (Riley et al. 2014).  This would also explain why some hatchlings in other, potentially colder nests, wait until warmer temperatures in spring.

 

How do hatchlings survive sub-zero temperatures in the nest? (They are supercool 😎)

Painted Turtle hatchlings are freeze tolerant to a certain degree and they are also capable of supercooling! For short periods, Painted Turtle hatchlings can tolerate their body tissues freezing at temperatures above -4℃.

But, even better than being able to tolerate body freezing, is to not freeze at all! Amazingly, Painted Turtle hatchlings are able to supercool their bodies to temperatures as low as -12 °C without actually having their body fluids freeze. The name for this process is supercooling.  (Paukstis et al. 1989, Packard and Packard 1993, Costanzo et al. 1999) and Painted Turtle hatchlings are able to do this because they do not have any “ice nucleating agents”  (INA’s) internally. INAs are particles that an ice crystal can form around. Therefore, for Painted Turtles,  freezing isn’t triggered in their bodies (Packard and Packard 1993), unless they come into direct contact with ice crystals or INA’s within the nest. Even still, their skin offers some protection from this occurring. Ironically then smaller turtles with less surface skin exposed may fair better than larger ones. Also, different substrate within the nest can buffer against soil moisture better than others and can limit ice crystal formation.

How do the features of their nest affect hatchlings’ ability to survive the winter?

The type of soil a female Painted Turtle chooses to dig her nest in can play a big role in determining whether or not the hatchings make it through the winter. During the winter, higher moisture in soils where the nests are dug, may put hatchlings at risk of coming into contact with ice crystals. Therefore, soils and sites that can remain dry will contain fewer ice crystals and are preferred locations. In areas where soil moisture is unavoidable, female Painted Turtles can still choose strategically in order to give the hatchings an advantage, by nesting in soils with more clay. Clay does not  allow much water to infiltrate and provide the necessary buffer against excess moisture (Costanzo et al. 2001).

What do hatchlings eat all winter?

Nothing! Hatchlings that remain in the nest can't eat or digest yet. Instead they rely on stored energy reserves to fuel them through the winter. Scientists used to think that leftover egg yolk was their main source of nutrition while overwintering in nests (Costanzo et al. 2008). However, research has revealed that remaining yolk from their yolk sac is primarily used up  within the first few weeks after hatching, and is almost gone by early Fall, so it cannot be the primary food source over the harsh winter months (Muir et al. 2013). Instead, energy reserves in their liver, other organs, and body tissues seem to play a key role in fueling hatchlings that remain in the nest over winter (Muir et al. 2013).

 Written by Meredith Karcz, Conservation Technician

 

 Download the article here: Do we go out, or stay in blog post. Overwintering hatchlings

References

 Birchard, G., & Packard, G. 1997. Cardiac Activity in Supercooled Hatchlings of the Painted Turtle (Chrysemys picta). Journal of Herpetology, 31(1), 166-169

 Carroll, Ultsch. 2007. Emergence Season and Survival in the Nest of Hatchling Turtles in Southcentral New Hampshire. Northeastern Naturalist 14(2), 307-310,

Costanzo J.P., J.B. Iverson, M.F. Wright, and R.E. Lee. 1995. Cold hardiness and overwintering strategies of hatchlings in an assemblage of northern turtles. Ecology 76:1772–1785

Costanzo, J. P., Dinkelacker, S. A., Iverson, J. B., & Lee, Jr, R. E. 2004. Physiological ecology of overwintering in the hatchling painted turtle: multiple-scale variation in response to environmental stress. Physiological and Biochemical Zoology, 77(1), 74-99.

Costanzo, J.P., Litzgus, J.D. and Lee Jr, R.E., 1999. Behavioral responses of hatchling painted turtles (Chrysemys picta) and snapping turtles (Chelydra serpentina) at subzero temperatures. Journal of thermal biology, 24(3), pp.161-166.

Costanzo, J. P., Litzgus, J. D., Larson, J. L., Iverson, J. B., & Lee Jr, R. E. 2001. Characteristics of nest soil, but not geographic origin, influence cold hardiness of hatchling painted turtles. Journal of Thermal Biology, 26(1), 65-73.

Costanzo, J. P., Lee Jr, R. E., & Ultsch, G. R. 2008. Physiological ecology of overwintering in hatchling turtles. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology, 309(6), 297-379.

Churchill, T. A., & Storey, K. B. 1991. Metabolic responses to freezing by organs of hatchling painted turtles Chrysemys picta marginata and C. p. bellii. Canadian journal of zoology, 69(12), 2978-2984.

Lovich, J. E., Ernst, C. H., Ernst, E. M., & Riley, J. L. 2014. A 21-year study of seasonal and interspecific variation of hatchling emergence in a Nearctic freshwater turtle community: to overwinter or not to overwinter?. Herpetological Monographs, 28(1), 93-109.

Muir,T. J.,Dishong,B. D.,Lee,R. E.,Jr and Costanzo,J. P. 2013. Energy use and management of energy reserves in hatchling turtles (Chrysemys picta) exposed to variable winter conditions. J. Therm. Biol.38, 324-330

Nagle, R. D., Kinney, O. M., Congdon, J. D., & Beck, C. W. 2000. Winter survivorship of hatchling painted turtles (Chrysemys picta) in Michigan. Canadian Journal of Zoology, 78(2), 226-233.

Obbard, M. E., & Brooks, R. J. 1981. Fate of Overwintered Clutches of the Common Snapping Turtle(Chelydra serpentina) in Algonquin Park, Ontario. Canadian field-naturalist. Ottawa ON, 95(3), 350-352.

Packard, G. C., & Packard, M. J. 1993. Hatchling painted turtles (Chrysemys picta) survive exposure to subzero temperatures during hibernation by avoiding freezing. Journal of Comparative Physiology B, 163(2), 147-152.

Paukstis, G. L., Shuman, R. D., & Janzen, F. J. 1989. Supercooling and freeze tolerance in hatchling painted turtles (Chrysemys picta). Canadian Journal of Zoology, 67(4), 1082-1084.

Riley, J. L., Tattersall, G. J., & Litzgus, J. D. 2014. Potential sources of intra-population variation in the overwintering strategy of painted turtle (Chrysemys picta) hatchlings. Journal of Experimental Biology, 217(23), 4174-4183.

Storey, K. B., Storey, J. M., Brooks, S. P., Churchill, T. A., & Brooks, R. J. (1988). Hatchling turtles survive freezing during winter hibernation. Proceedings of the National Academy of Sciences of the United States of America, 85(21), 8350–8354. doi:10.1073/pnas.85.21.8350

Vali G. 1995. Principles of ice nucleation. Pp. 1–28 in R.E. Lee, Jr.,G.J.Warren,and

L.V Gusta,eds.BiologicalIceNucleation and Its Applications. AmericanPhytopathologicalSociety,St. Paul, Minn.

 

 

 

 

 

 

 

Wrapped in Plastic. The Global Problem and How You Can Help

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Mert Guller

Plastic, which comes from the Greek verb plassein that translates to “to mould or shape,” was invented and made popular in 1869 by John Wesley Wyatt. This new material offered an alternative from the natural resources humans were confined to, such as metal and wood, along with animal based resources such as ivory, coral or bone. In plastic’s infancy it was used to mimic ivory and turtle shells and it was used for items such as billiard balls, piano keys, combs and so on. Over the years, new plastic variants were developed. A large-leap occurred after the end of World War 2 where production exploded due to it being cheap, convenient and because it was easy to mass produce. This efficiency resulted in the rise of the “throw away” society we live in today.

Brian Yurasits

A research article published in Science Advances 2017 titled “Production, use, and fate of all plastics ever made” estimates that in 2015, all plastic that has ever been produced from raw materials amasses 6300 million metric tons. Further that from all that plastic only 9% has been recycled, 12% has been burned, and the remaining 79% has ended up in landfills or the environment. The researchers further project that if current habits continue, 12000 million metric tons of plastic will be in landfills or the environment by 2050. The article also goes on to mention that 42% (146 million tons) of all the plastic created in 2015 was for packaging. Building and construction materials (which are long-lived practical uses for plastic as opposed to single-use packaging) represent only 19% of the share. The situation is dire! Which has propelled many companies, cities and even countries to begin to tackle the issue...starting with the biggest culprit of single-use plastics such as shopping bags, packaging, straws and utensils. These common items, which we come across in our everyday lives, add convenience, but compared to the small amount of time they are in our hands, the time they last in landfills or the environment is an eternity.

There are many small and easy ways that each person can reduce their plastic footprint, and yet make a huge difference:

  1. Reusable coffee cups/mugs - Grab yourself a nice personal travel mug, you can get them in many styles and often coffee shops will offer discounts to people that use a reusable vessel
  2. Metal or glass water bottles - Ditching plastic water bottles is one of the best things you can do to reduce your footprint- Not only can you get very nice ones which are able to keep your water cold for hours, but refill stations are often easily found in public areas. Furthermore, the quality of your town water is monitored closely, while water bottling companies aren't bound by the same standards.
  3. Reusable shopping bags - The hardest thing about reusable shopping bags is remembering to take them into the store. However, they are extremely cheap and come in a variety of styles and materials. And with stores starting to charge for bags you’ll save money in the long run as well reduce your plastic footprint. The reusable bags are also a much sturdier option for carrying your purchases. So many people are carrying these that they are traded around readily, and you never know, but another shopper might be willing to share!  Finally, as a last resort, some stores offer paper bag options.

Tips from the Land Between staff:

  1. Personal care options - Shampoo bars are an excellent alternative to bottled versions and they often have no packaging. Look for stores that have a return/reuse/refill options for the containers for cosmetics such as creams, lotions and soaps. More and more specialty stores and health food stores offer these options. We hope that soon grocery stores will get on this wagon too.
  2. Produce and bulk shopping - You don’t need produce bags, just put your loose produce in the cart. Alternatively, cloth drawstring bags are easy to sew and you can make them from old clothes too! They are becoming increasingly available in grocery stores. Also they don’t add significant weight to your produce when placed on the scales at the checkout counters. You can even use old stockings or socks for produce. Also, try shopping at bulk stores where you can bring your own containers, this adds use to those plastic containers you already have stocked up.
  3. Litterless lunches – Bring your meals in reusable options such as containers and reusable snack/sandwich bags such as those made with beeswax. This also pairs well with the next tip: bring your own ‘city kit’ for take out when dining out- a kit has a take-out container, personal cutlery and a travel cup.
  4. Garbage disposal options - Use a biodegradable garbage bag and if you throw away wet materials that cannot be composted, you can line the bag with a standard plastic one; then when you visit the dump or put the garbage out, you can remove the biodegradable one and rinse and reuse the plastic one as a liner again and again.
  5. General tip - Just be a little more conscious of your purchasing habits every time you go to the store. Try to find items with the lowest amounts of packaging or wrapping and if it is difficult to avoid, look for bulk sizes, so that you can to maximize the volume to packaging ratio.

Many people might think that reducing waste is a daunting or difficult goal to achieve, but small steps work! You don’t have to jump right in, just make a few minor changes that you can stick to at first, and over time new habits will be made. Also each step and each piece that is saved from the landfills is cumulative. In no time at all, you will have made a significant impact. In 2010 the average Canadian produced 32.85 kilograms (72.42 pounds) of plastic waste. With a few of the minor habit changes listed above a few pounds can easily be shaved off.

If you are having a hard time imagining that a person could generate that much plastic waste in one year, check out this news article about Daniel Webb. He is a British artist who kept every bit of plastic waste that he generated in 2017 which tallied up to 29 kilograms (63.93 pounds), very close to our Canadian average...and only 10% of it was recyclable. He made a wall of his plastic waste! See it here:

https://www.theguardian.com/environment/2018/apr/17/i-kept-all-my-plastic-year-4490-items-forced-rethink

 

 

Sources:

https://www.scientificamerican.com/article/a-brief-history-of-plastic-world-conquest/

https://www.sciencehistory.org/the-history-and-future-of-plastics

https://ourworldindata.org/plastic-pollution

https://advances.sciencemag.org/content/3/7/e1700782.full

Mr. Misunderstood. Snapping Turtles are Not so Scary and Very Important

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By Meredith Karcz, Conservation Technician

For many people, encountering a snapping turtle while swimming, on the road, or on the land can be a scary experience. Many people fear that the turtle will snap at them, and that their bite will take off a finger or toe! Fear of this species is common because of the misconception that the Common Snapping Turtle (the only Snapping turtle found in Canada), is aggressive. But, in reality, the Common Snapping Turtle is not aggressive at all. In water, they will completely avoid confrontation by burying themselves in sediment or swimming away when they feel the least bit intimidated. And on land, they only act in defense- and even then, they are not as harmful as you may think.

When on land, Snapping Turtles are not able to escape quickly or hide when they encounter a threat because unlike other turtles, Snapping Turtles cannot retreat into their shells for protection. Their large head, tail, and limbs do not fit inside their shell- their bottom shell (plastron) is relatively too small as compared to other turtles. So when they feel threatened by a potential predator on land, they will snap out of self-defense – but not because of aggression or for any hunting instincts. Also, even if they snap at you, they cannot take off a finger or a toe because Common Snapping turtle beak’s do not have the required jaw strength: their average strength is 208-226 Newton. Meanwhile adult humans with molars are between 280 and 300 Newton. This means that a Common Snapping Turtle, may be able to break skin, but cannot bite through ligaments. In fact, they cannot even break an average carrot in half.

As long as you respect a Common Snapping Turtle’s space when on land, or if you encounter them when they are in water, a Snapping Turtle will have no reason to be defensive. So now, that you are not as nervous, you may wish to approach a turtle on land to help it across roads for instance. An important thing to know is that you should never lift a turtle by its tail! A turtle’s tail is part of their spine, and lifting them this way can dislocate their spine and cause permanent damage. Other useful facts are that Snapping Turtles cannot reach their heads behind their back legs or under their shells. This means there are ways to lift them or handle them without fear of their snap! Check out the Turtle Guardians website, or partner websites for instructional videos.

Now that we have dispelled the myth that Common Snapping Turtles are scary, let’s talk about why they are so important. Snapping turtles are the best cleaning crews for our lakes and ponds. When snapping turtles are in lakes, we have more assurance that the water is safe for swimming. This is because, while Snapping Turtles are omnivores, eating both plants and animals and including fish, frogs, insects, crayfish, and even small birds, they are also amazing scavengers. Snappers eat any dead and decaying animals they find along the bottom of lake and ponds. By removing decaying and potentially diseased animals, they play a vital and irreplaceable role in keeping the water healthy and free of harmful bacteria.

Turtles are also essential to the future health of our aquatic ecosystems in other ways: They spread seeds! This critical and essential ecological service provided by Snapping Turtles (and other turtles) means that there are more aquatic plants to filter nutrients, clean water, and provide fish habitat in our lakes and wetlands for future generations. How do they do this? Aquatic plants and seeds make up a large portion of the Common Snapping Turtle’s diet. Researchers have found that seeds which have passed through a turtle’s gut will germinate successfully (Kimmons and Moll 2010). Considering that Snapping Turtles will migrate up to 3.9 km to return to hibernation sites, and that females will travel up to 2 km to nesting sites, this species’ capability of dispersing aquatic plant species is significant (Brown and Brooks 1994, Petit et al. 1995). The seeds that they spread result in a proliferation of aquatic vegetation, which in turn, provides habitat and food for many species, prevents shoreline erosion, adds oxygen to the water, removes excess nutrients from the water column helping to keep algal blooms in check, and more.  Snapping Turtles’ integral role of spreading seeds helps to keep aquatic communities healthy and diverse.

So the next time you encounter a Snapping Turtle, remind yourself that there is no reason to be afraid of this awesome animal. Instead, from a respectful distance, muse at its fine details, such as the three rows of triangular bony plates on its dinosaur-like tail, its smiling beak, bright eyes, or angular shell (carapace). This species of turtle descends from ancestors who roamed the earth during the Late Cretaceous Period alongside the dinosaurs. Your next chance to spot Snapping Turtles in The Land Between will be in the spring- in early May as they emerge from their overwintering sites. Watch for them along roads and if it is safe to do so, help them across, because they are important and irreplaceable helpers. Weed them to stick around!

If you see a Snapping Turtle, note the location, take a picture and report the observation through our Turtle Guardian App or at https://www.turtleguardians.com/sighting-report-form/ so that we can understand where to install crossing signs, turtle tunnel fencing, and which habitats need to be conserved.

Download the article here- Mr. Misunderstood

References

Brown, G.P., and R.J. Brooks. 1994. Characteristics of and fidelity to hibernacula in a northern population of Snapping Turtles, Chelydra serpentina. Copeia 1994(1): 222-226.

Environment and Climate Change Canada. 2016. Management Plan for the Snapping Turtle (Chelydra serpentina) in Canada [Proposed]. Species at Risk Act Management Plan Series. Ottawa, Environment and Climate Change Canada, Ottawa, iv + 39 p.

Joyce, W. 2016. A Review of the Fossil Record of Turtles of the Clade Pan-Chelydridae. Bulletin of the Peabody Museum of Natural History 57(1):21–56.

Kimmons, J. B., and D. Moll. 2010. Seed dispersal by Redeared Sliders (Trachemys scripta elegans) and Common Snapping Turtles (Chelydra serpentina). Chelonian Conservation and Biology 9: 289–294.

Pettit, K. E., C. A. Bishop, and R. J. Brooks. 1995. Home range and movements of the common snapping turtle, Chelydra serpentina serpentina, in a coastal wetland of Hamilton Harbour, Lake Ontario, Canada. Canadian Field Naturalist 109(2): 192-200.

Takaki, P., Vieira, M., & Bommarito, S. (2014). Maximum bite force analysis in different age groups. International archives of otorhinolaryngology, 18(3), 272–276

Herrel et al. 2002. Evolution of bite performance in turtles. Journal of Evolutionary Biology.

Overwintering Turtles- How Turtles Hibernate

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Shawn Hill Photography

Written by: Ally Lahey, Citizen Science Coordinator

Colder temperatures mean one thing: winter is on its way. For animals and people, that means a lot of prep-work. Turtles are no exception. In fact, turtles use some incredibly unique methods to get through the winter. From using their rear-ends to breath, to forgoing oxygen altogether, and even using their shells as “Tums” to aid cramps, turtles have come up with fascinating solutions for freezing temperatures. The amazing things they do in order to survive the winter proves that turtles are, quite literally, the coolest!

Before we jump into all the amazing facts about how turtles overwinter, let’s review the basics. 

Turtles are ectotherms, or “cold blooded.” This means that instead of producing their own body heat, ectotherms rely on their environments. So, whatever temperature it is in its surroundings, is the same as the internal temperature of a turtle (or any ectotherm). That’s why you’ll see turtles basking on logs or on the sides of roads—that’s how they get warm and allow their bodies to regulate normally. Since turtles rely on their surroundings for their internal body temperatures, that means that when the temperatures start getting colder, turtles get just as cold. The implications of being an ectotherm has led to the strategy turtles have developed in order to make it through the winter. 

Adult turtles are not able to survive anything below 0° C, because the water in their bodies would crystallize and expand- and they would freeze to death. Therefore, turtles have to find places that are just above freezing temperatures to spend the winter. Luckily, deeper bodies of water such as ponds, lakes, and wetlands don’t freeze all the way through. Often, if the water is deep enough, only the part of the water closest to the surface freezes and forms a sheet of ice; meanwhile, the water below, near the bottom of lakes and ponds, remains above 0° C. This is lucky for turtles. However, turtles still have to  adjust and adapt to being so cold. 

Unlike us endotherms that can regulate their own temperature internally (most animals and humans too), turtles can’t put on layers to stay warm. When they get cold, everything slows down in their bodies. Their metabolism hits the breaks dramatically, their hearts slow down and beat extremely slowly at one beat every few minutes! They also have reduced immune-system functions and are more prone to any diseases. And during hibernation, they don’t require as much oxygen. 

Not needing to breath normally is pretty handy, considering there’s a thick brim of ice preventing them from coming up for air. So how do turtles breathe if they can’t come to the top of the water to fill their lungs with oxygen? The answer is fascinating. During hibernation turtles will develop highly vascularized tissue on their bodies that allows oxygen to be absorbed through their skin. The area that experiences this vascularization the most is in their cloaca- the cloaca is basically their bum!  That’s right. You read that correctly. During hibernation, turtles breathe through their rear-ends. The formal term for this is “cloacal respiration.”

Unfortunately, even with their fancy schmancy “cloacal respiration” getting through the cold months comes with other obstacles bum-breathing can’t solve. Quite often, the bodies of water that turtles will overwinter in have other creatures in it too. That means that the oxygen underneath the ice is limited, and it can run out completely. Also, if water bodies that they are wintering in experience changes in water depth over the winter from dam-drawdowns, this can limit the oxygen further. 

To prove, once again, that turtles are the coolest creatures, they developed another way of surviving, even when their oxygen runs out! In these times, turtles literally switch their metabolisms to another system; one that doesn’t need oxygen at all. Even more fascinating; researchers have found in the lab that turtles can use this other metabolism—that doesn’t use oxygen—for up to 100 days! Of course, an impressive feat like switching a metabolism doesn’t happen easily. When turtles burn their energy reserves without oxygen (in hypoxic situations), lactic acid builds up in their bodies. Humans experience lactic acid build up too: it’s what causes cramps in muscles after exercise. This is as uncomfortable for turtles as it would be for us- and the way they deal with it is incredible. Once again, turtles rise to the challenge and have developed a unique method for keeping lactic acid build up at bay- by using their shells! That’s right, turtles use their shells, specifically the calcium they store inside of it, in order to neutralize the acid, and subdue and calm their cramps. Just like a calcium-rich antacid you would take for heartburn, turtles use the calcium from their shells to deal with the lactic acid building up in their bodies. Too cool!

Now, surviving without oxygen in hibernation is limited to a few months and also dealing with lactic acid build up has its limitations: Near the end of winter, turtles get quite uncomfortable. In fact, when they finally emerge from hibernation, they will often be quite disoriented from any excess build up of acid and from the discomfort associated with it. Therefore, turtles in spring look immediately to warm up (whether on rocks or on roads) in order to revv up their metabolism and rid their bodies of remaining lactic acid and discomfort. This is important to understand because it means turtles need us to keep an eye out for them once they finish hibernating. With so much of their already energy depleted and their entire focus put towards getting warmer, turtles coming out of hibernation aren’t always aware of their surroundings. That means, even before nesting season, us Turtle Guardians need to keep an eye out for groggy, cramped turtles that might be on roads trying to get warm!

 

Here are other ways you can help turtles with hibernating:

-Protect the water they hibernate in! Don’t let water levels get too low in frozen ponds or wetlands where turtles are overwintering. If water gets too low, the oxygen and warmer layer below will be diminished or the water will freeze solid and that means the turtles underneath in the muck may die. 

-If you see a turtle underneath the ice, let it be! Turtles know what they are doing. It might seem impossible, but turtles know how to handle the winter months. It can be dangerous to try and “save” a hibernating turtle by removing them from the water underneath the ice and exposing them to the cold winter air. 

- Don’t take turtles out of the natural environment or move them from their natural territories; turtles know where they hibernate. They have dedicated hibernation sites. When moved, turtles will try desperately to return to these sites and will often die trying to get home. 

- Young hatchlings need to find hibernation sites. They have approximately three years to imprint routes, hibernation areas, feeding grounds, and territories into their minds. Let them be in the natural world so they can imprint these areas and survive into adulthood. 

- Don’t pollute aquatic environments; turtles are more susceptible to pollution and disease in the winter months. Studies have shown that plastics and additives have implications for our and wildlife immune systems; and nitrates can also compromise immune systems. Don’t flush toxins into septic systems or into water systems. 

- Don’t release pet turtles (often red-eared sliders) into the environment. They don’t know how or where to hibernate and they may carry and spread diseases such as herpes. 

https://www.northcountrypublicradio.org/news/story/24195/20190117/natural-selections-how-do-turtles-survive-a-winter-underwater

https://blog.nature.org/science/2017/01/30/turtles-under-ice-winter-survival-hibernation-adaptation/

https://www.fieldecology.com/blog/winter-turtles

http://archive-srel.uga.edu/outreach/ecoviews/ecoview090215.htm

http://theconversation.com/the-secret-to-turtle-hibernation-butt-breathing-86727

 

Turtles: The Coolest Navigators!

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Turtles: The Coolest Navigators!

Written by: Ally Lahey, Citizen Science Coordinator

If you’re a Turtle Guardian, you’re most likely familiar with at least some of the threats that turtles face, but have you ever wondered how turtles navigate through these dangerous surroundings? Well, the answer is much more multifaceted than you may have guessed! Turtles use a complex mix of features to get around their environments, and scientists are just starting to understand the different mechanisms turtles use. From magnetic fields, the position of the sun, and spatial memory/learning, turtles have fascinating abilities to help them survive…but these abilities can be used against them when people try to help without being properly informed.

Although there is much more to learn and discover, so far scientists know of at least 3 modalities that turtles use to locate their home turf, and themselves within it:

The first uses Earth’s magnetic fields (magnetoreception). Turtles are just one of many animals that use magnetoreception and researchers have found that there are two possible ways they sense the magnetic field. One way is with magnetite, which are iron clusters with strong magnetism thought to be connected to the nervous system. The other way is with a protein, called a cryptochrome, that is located in their eye. Cryptochromes have special pairs of electrons that are excited by sunlight and spin around each other when they’re exposed to certain wavelengths of light. This spinning causes turtles to have the ability to detect very weak magnetic fields such as that of the Earth (only 0.5 gauss!).

The next modality is the position of the sun. Within a day of hatching, turtles develop the ability to use only the position of the sun in order to move to where they’re going. In a recent study that investigated how hatchling Blanding’s Turtles navigated, researchers found that the position of the sun was used in order to move to wetlands upon hatching. In order to ensure the turtles were not using their geomagnetic forces to determine how to travel, the hatchlings had a magnet attached to their shells to disrupt that sense. The researchers also blocked the turtles’ ability to see the wetland by placing them in a field with large cornstalks.  After the researchers determined what direction the baby turtles had initially been heading, they were collected and held in a laboratory where half of the turtles experienced a simulation of normal daylight hours, while the other half experienced daylight hours that were six hours behind. When placed back into the field where they were collected, the turtles that experienced normal daylight hours moved as normal toward the direction of the wetland. However, the turtles that experienced daylight that was shifted six hours behind moved in a direction that was 90 degrees from their initial trajectory. The researchers said this made sense since 90 degrees is a quarter of 360, and a quarter of an entire day is 6 hours.

The last modality is through learning and memory. In a recent study of Painted Turtles, scientists moved individuals to a completely new location to test their ability to respond to changes in their habitats. The results were surprising and have important implications. They found that the young juvenile turtles, those under four years old, were able to readapt to the changes in the habitat and navigate successfully within it, locating far off water sources and moving through the landscape with the precision of the turtles local to the area. This was not the case for turtles older than four years of age. Unlike the young juveniles, the older turtles were not about to adapt to the change in habitat. This supports that turtles have a certain window of time in which they imprint on their habitat and it becomes their home. The researchers attributed this to the neurotransmitter acetylcholine, which influences spatial memory in animals. This was then put to the test by giving turtles a drug that temporarily blocked acetylcholine receptors, thus blocking their ability to access long-term spatial memory. What they found was fascinating! The young group of turtles were able to navigate through their environments with no changes whatsoever, whereas the older group of turtles were unable to navigate at all and “wandered aimlessly” until the drug wore off. This offers support that turtles form and utilize spatial memories in the first few years of life in order to navigate their surroundings and successfully migrate. This was the first time such a complex form of cognition during migration was found for reptiles.

 

So what does this mean for Turtle Guardians, or anyone who wants to help turtles? Most importantly, if you come across an adult turtle (over four years), do not move it or relocate it. Turtles are tied to their home habitats! Once they imprint on their “homes” they cannot be placed anywhere new or they will not survive. They will not know where to nest, where to hibernate or where to find food.

We now know of three different ways turtles are connected to their birth territories and navigate within it. With so much more to learn about turtle navigation, our understanding of the importance of their territories to their survival will only grow.

 

What you can do to help:

  • Unless a turtle is on a road, the best rule of thumb is to leave it alone. Do not remove a healthy turtle from the wild. Do not relocate turtles from lakes, ponds or other areas.
  • Displaced adult turtles will stop at nothing to return to their home territory, forgoing hibernation and even eating while trying to find their home. Moving an adult turtle from their home territory is akin to killing it.
  • Understand that a turtle’s home range and routes can be extensive. If you come across a turtle that is injured or sick, make a note of the location where it was found so that it can be returned to this its home upon recovery. The more precise, the better!
  • If you find hatchling or young juvenile turtles on the road, do not take the turtles home! The hatchling needs to orient itself finding hibernation, feeding, and basking areas so that it can survive as an adult. Turtle Guardians recommends moving them to the nearest wetland from where they were found. Try to stay within 250-500m maximum when transporting them to the closest wetland. Keeping them close to their nest sites also ensures that the integrity of the genetic diversity within the population is sound and maintained.
  • If a turtle is on the road, with your safety and the safety of other drivers in mind, move the turtle in the direction it is heading. Turtles are stubborn--they will turn around and double-back across the road if they’re not moved toward where they were heading.
  • Get involved by becoming a turtle guardian!
  • Learn about and support provincial and federal legislation that protects the habitat for all 8 of Ontario’s at-risk turtles.
  • Talk about turtles! If you care for turtles, share that love with others. Turtles are endlessly fascinating and cool! Tell others about cool turtle facts or about the dangers turtles are facing and how all 8 of Ontario’s turtles are species at-risk. Not everyone knows what turtles are up against or how to help, so share your knowledge and enthusiasm!

Download the full article here: Turtles- The Coolest Navigators

Sources:

https://waldenspuddle.org/help-for-turtles/

https://blogs.scientificamerican.com/observations/how-a-painted-turtle-finds-its-way/

https://www.sciencedaily.com/releases/2018/11/181109101427.htm

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0124728

RED: Red Eared Sliders. They can hurt the environment but are also harmed by us.

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Post by: Kelly Wallace of Think Turtle Conservation Initiative in Bancroft; a partner of the Turtle Guardian's Program

RED-EARED SLIDERS

Prompted by the Think Turtle post on 21/10/2018 the following article is to do with the red-eared slider and why I view this turtle species as the "underdog" of the turtle world. This is in fact a topic I have wanted to write about for a while but have been too busy.

First, please note that it is illegal to possess any of the eight turtle species native to Ontario and this includes the painted turtle that people have been known to confuse with red-eared sliders. Sliders are notably different with the distinct red stripe on both sides of it's head. They are not a turtle species native to Ontario and are instead originally from the Mississippi River and Gulf of Mexico but now found worldwide. In Ontario they are available to purchase as pets but are not as readily available in pet stores as they once were.

Sadly people purchase sliders when they are cute and small not giving much thought to the fact that they could grow to 12" (30.48 cm) in length which involves tank size upgrades (10 gallons per 1 inch of shell), a filtration system and special UVB reptile lighting is needed, in captivity a well cared for healthy slider can live, 20, 30 even 40 years making them a long term commitment and with this there is of course the ongoing financial outlay. Sliders kept as pets to some are considered smelly, Salmonella is a concern with prevention easily remedied but kids/adults that do not wash their hands after handling turtles run the risk of being infected, as well turtles are messy eaters and in truth no filtration system can truly keep up with the larger sized sliders, a separate feeding tank can help with that but again adds to the cost and chores for the owner. It is often children that sliders are purchased for as a starter pet and when the child loses interest or as the responsibilities become more then expected the turtle is viewed as a burden.

As a result of this many red-eared sliders are given up on, some are responsibly submitted to rescue centers such as The Little RES Q in Pefferlaw, Ontario that hopefully go on to get adopted, others are unfortunately released into the wild where they are considered an invasive species. Depending on the state of a sliders health if released into the wild they may infect an otherwise healthy turtle population in the area they are released and/or once in the wild their behavior can become quite aggressive towards other turtles resulting in competing for food and very possibly pushing the native turtle species out of the area. I think of this as if a turtle spent the first part of it's life in an aquarium and then was released into the wild it is not surprising that they would go hog wild with the prospect of their new much more appealing environment.

There are also incidents in the pet trade of pet stores being supplied sickly turtles by breeders, further to this there are pet stores that do not routinely quarantine turtles for a period of time to ensure they are healthy followed by unsuspecting customers being sold turtles that die prematurely. Likely due to over breeding young red-eared sliders dying is prevalent and some pet stores even offer a plan that if you pay an extra fee and your slider dies within a certain amount of time the turtle will be replaced. I always try to encourage people not to buy sliders as pets because of the reasons previously mentioned but if they are fixed on this then I ask them to please adopt. There are red-eared-sliders posted on Kijiji available to adopt, however you get what you pay for including possibly a unhealthy turtle, the best place to adopt a slider is through The Little RES Q. They have quite a few adoption kiosks set-up and there is a map on their Facebook page.

Over the years due to legal and illegal practices red-eared sliders have suffered considerably. In some parts of the world baby red eared sliders are farmed by the millions and shipped to pet stores globally, larger sliders possibly end up at meat markets. These activities and more have contributed to sliders being noted as health and environmental threats. Sliders confiscated by authorities via illegal trade in some countries are euthanized by freezing and other means. This is a turtle species that is caught in the vicious cycle of consumer supply and demand and as much as it pangs me to say this if people globally continue to purchase sliders their fate as outlined will continue.

In China red-eared sliders have been the victim of cruel practices for years. One being live sliders are packaged in a sealed plastic pouches with a small amount of colored water and sold as necklaces and key chains. This is aimed at the tourist trade with the idea being these trinkets will bring good luck to the purchaser. Merchants have been documented justifying this by stating that the purchaser can let the turtle go and keep the turtle. In truth, after the sellers get their money there is no regard for what happens to the turtles. Most turtles would suffer severe stress, starve, suffocate and die in their own feces infested water. There are no animal welfare laws in China protecting turtles or other animals against such hideous treatment. Attempts have been made to ban this cruel practice but to date they have been unsuccessful. There is a petition to sign if you feel inclined. Google ...Live Animals Are Still Being Sold in Key-chains and Mobile Phone Trinkets – Let’s Stop This NOW!

How anyone could treat any animal in such a way or purchase something of this nature defies understanding.

The thought of what goes on with red-eared sliders is disheartening and why I stand by my claim that they are the underdogs of the turtle world through no fault of their own. Please know that I am well aware there are plenty of people that have red-eared sliders as pets and do right by them. I am so thankful of these people that are intent on providing their slider(s) with the best possible care and are it it for the duration. I love red-eared sliders dearly and have fond memories of the ones I had when I was growing up until I was forced to give them up.

In conclusion, the efforts The Little RES Q makes to look out for red-eared sliders and locate good homes for them is to be admired. One day I hope to be in a position where I can provide a good home for a couple of adopted sliders myself but that time is not now I am far too busy. If you are thinking of adopting please do so responsibly knowing all the responsibilities this entails before making that decision. Thank you.

Kindest Regards,
Kelly Wallace
Think Turtle Conservation Initiative
thinkturtle@yahoo.com
Facebook: thinkturtleci

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