Turtles in Southern Ontario
Jarmila Becka Lee, Conservation Grants Manager for WWF-Canada’s Endangered Species Recovery Fund (ESRF), and Lenore Nadeau, Education Officer, visited one of our ESRF projects this past September. Here is Jarmila’s description of their day in the field:
Early on a cloudy September morning, we set out for Rondeau Provincial Park to visit Ryan Bolton, a PhD student on Dr. Ron Brooks’s research team at the University of Guelph. With the support of the ESRF, Ryan and Dr. Brooks are researching turtles at risk in southern Ontario. The researchers’ ultimate goal is to prevent further declines in these turtle populations, which, despite parks and other protected areas, have a very low hatching success rate.
Building on previous studies in the area, the current work focuses on identifying nest predators and increasing the number of successfully hatched eggs. The researchers move the turtle nests to special large enclosures fitted with cameras and record which animals are getting at the nests. Once this is determined, an action plan can be developed to keep those predators away. The researchers also gather a number of eggs from the turtle nests and take them to the lab to hatch – away from any predators. The resulting hatchlings are then released at suitable sites along the shores of Rondeau Bay.
Our task that day was to help Ryan release 50 to 60 spiny softshell, Blanding’s and northern map turtle hatchlings. After meeting Ryan, we loaded the gear and turtle hatchlings (about a week old) into a small motorboat and headed to the release sites across the bay. The steady rain may have helped to prevent immediate predation by shorebirds. Giving the tiny hatchlings a helping hand in their new environment – a shallow, weedy bay – was quite a thrill.
During the return boat ride, the skies really opened up; the wind increased and waves swept over the edge of the bow; a heavy fog had set in. We were soaked but would not have traded our adventure for anything. Spending time with Ryan and the turtles was a special experience. We were lucky to have a first-hand look at how WWF-Canada's supporters are helping in this crucial work to recover these at-risk turtles.
Turtle Facts
Blanding's Turtle
The Blanding’s turtle is medium sized with a shell (carapace) length between 15 and 25 cm. They are semi-aquatic and somewhat highly domed compared to other turtles in Ontario. The shell is dark and often scattered with white or yellow flecks or dots. Blanding’s turtles have a very long neck and the underside is a bright lemon-yellow.
Cool fact: Blanding's turtles are often referred to as "semi-box" turtles because, like the box turtle, they have a hinge on their lower shell (plastron) so that both ends can close tighter against the carapace when the turtle withdraws into its shell for protection.
Spiny Softshell Turtle
Named for the fleshy, spine-like protuberances on the front portion of the soft and leathery shell, spiny softshell turtles are medium to large-sized freshwater turtles. This species is characterised by a flattened body and a long, flexible neck and head with a tubular snout. The flattening of the body is likely an adaptation to facilitate burrowing in the sand and mud at the bottom of various bodies of water, which makes the turtle better able to conceal itself. In shallow waters, the long, flexible neck and tubular snout are used to reach the surface to breathe while the rest of the turtle remains buried. Females are larger than males and range in length from 18 to 54 cm, whereas males have a shell (carapace) length of 12.5 to 24 cm.
Cool fact:This is one of the very few turtle species where sex can be identified at hatching. Many other turtles are dependent on temperature to determine sex but the sex of spiny softshell turtles is determined genetically. Hatchling males can be identified by the sharply defined circular spots on the carapace; females have less defined, blotchy spots.
Northern Map Turtle
The northern map turtle’s shell (carapace) is olive or grayish brown and broad. The underside of the turtle is a light yellow/cream colour. The head, neck and limbs are dark olive, brown or black with thin yellow or green stripes. There is also a circular spot behind the eye of most turtles. Females are considerably larger than males, shell lengths ranging range from 18 to 27 cm while males range from 9 to 17 cm.
Cool fact:The scientific name "geographica" and the common name "map" turtle refer to the markings on the carapace. Each scute exhibits a swirling array of thin, coloured lines that resemble a topographical map or waterways on a chart.
More information about Ryan’s project
The goal of this project is to assess the impact of mammalian depredation and dipteran infestation (egg and embryo parasitism by the larvae of a species of flesh fly) for three turtle species at risk (spiny softshells, Blanding’s turtles and northern map turtles) at Rondeau Provincial Park. A primary limiting factor for these turtle species is reproductive success. Critical nesting areas are threatened by anthropogenic disturbance – recreation, development, vandalism, erosion, etc. Human recreation (boating, swimming, walking, etc.) is common on or near the nesting beach at Rondeau. These threats are compounded by a potentially high rate of embryo/hatchling mortality from predators, including flesh flies.
These threats are being assessed so that mitigation procedures can be comparatively tested in order to increase population growth and sustainability. The mitigation methods include the translocation of nests to large-scale predator exclosures, translocation of nests to random sites, scent dispersal at nest-sites and artificial incubation. Also, factors involved in turtle nest-site selection and the life-history of the species of flesh fly will be thoroughly examined.
Rondeau Provincial Park is experiencing nearly 100% depredation of all turtle nests within the project area. Although nesting activity is currently high, the adult turtles in these populations are likely old individuals; however, since recruitment (when a new sexually reproductive individual enters the population) is dependent on embryo hatch success and embryo hatch success is currently near or at 0%, the population will crash when these older turtles die. Therefore, completely assessing the threats and developing recovery actions must be completed in this relatively short period of time when large numbers of sexually reproductive turtles remain in these populations.
The positive impact on the recovery of these species is an increase in embryo hatch success. By increasing the hatch success of turtle eggs in this population, more hatchlings will enter the ecosystem and there will be a corresponding increase in the likelihood of successful recruitment. Data from this study will be used to inform recovery teams and this research will aid in the development of recovery initiatives.
Early on a cloudy September morning, we set out for Rondeau Provincial Park to visit Ryan Bolton, a PhD student on Dr. Ron Brooks’s research team at the University of Guelph. With the support of the ESRF, Ryan and Dr. Brooks are researching turtles at risk in southern Ontario. The researchers’ ultimate goal is to prevent further declines in these turtle populations, which, despite parks and other protected areas, have a very low hatching success rate.
Building on previous studies in the area, the current work focuses on identifying nest predators and increasing the number of successfully hatched eggs. The researchers move the turtle nests to special large enclosures fitted with cameras and record which animals are getting at the nests. Once this is determined, an action plan can be developed to keep those predators away. The researchers also gather a number of eggs from the turtle nests and take them to the lab to hatch – away from any predators. The resulting hatchlings are then released at suitable sites along the shores of Rondeau Bay.
Our task that day was to help Ryan release 50 to 60 spiny softshell, Blanding’s and northern map turtle hatchlings. After meeting Ryan, we loaded the gear and turtle hatchlings (about a week old) into a small motorboat and headed to the release sites across the bay. The steady rain may have helped to prevent immediate predation by shorebirds. Giving the tiny hatchlings a helping hand in their new environment – a shallow, weedy bay – was quite a thrill.
During the return boat ride, the skies really opened up; the wind increased and waves swept over the edge of the bow; a heavy fog had set in. We were soaked but would not have traded our adventure for anything. Spending time with Ryan and the turtles was a special experience. We were lucky to have a first-hand look at how WWF-Canada's supporters are helping in this crucial work to recover these at-risk turtles.
Turtle Facts
Blanding's Turtle
The Blanding’s turtle is medium sized with a shell (carapace) length between 15 and 25 cm. They are semi-aquatic and somewhat highly domed compared to other turtles in Ontario. The shell is dark and often scattered with white or yellow flecks or dots. Blanding’s turtles have a very long neck and the underside is a bright lemon-yellow.
Cool fact: Blanding's turtles are often referred to as "semi-box" turtles because, like the box turtle, they have a hinge on their lower shell (plastron) so that both ends can close tighter against the carapace when the turtle withdraws into its shell for protection.
Spiny Softshell Turtle
Named for the fleshy, spine-like protuberances on the front portion of the soft and leathery shell, spiny softshell turtles are medium to large-sized freshwater turtles. This species is characterised by a flattened body and a long, flexible neck and head with a tubular snout. The flattening of the body is likely an adaptation to facilitate burrowing in the sand and mud at the bottom of various bodies of water, which makes the turtle better able to conceal itself. In shallow waters, the long, flexible neck and tubular snout are used to reach the surface to breathe while the rest of the turtle remains buried. Females are larger than males and range in length from 18 to 54 cm, whereas males have a shell (carapace) length of 12.5 to 24 cm.
Cool fact:This is one of the very few turtle species where sex can be identified at hatching. Many other turtles are dependent on temperature to determine sex but the sex of spiny softshell turtles is determined genetically. Hatchling males can be identified by the sharply defined circular spots on the carapace; females have less defined, blotchy spots.
Northern Map Turtle
The northern map turtle’s shell (carapace) is olive or grayish brown and broad. The underside of the turtle is a light yellow/cream colour. The head, neck and limbs are dark olive, brown or black with thin yellow or green stripes. There is also a circular spot behind the eye of most turtles. Females are considerably larger than males, shell lengths ranging range from 18 to 27 cm while males range from 9 to 17 cm.
Cool fact:The scientific name "geographica" and the common name "map" turtle refer to the markings on the carapace. Each scute exhibits a swirling array of thin, coloured lines that resemble a topographical map or waterways on a chart.
More information about Ryan’s project
The goal of this project is to assess the impact of mammalian depredation and dipteran infestation (egg and embryo parasitism by the larvae of a species of flesh fly) for three turtle species at risk (spiny softshells, Blanding’s turtles and northern map turtles) at Rondeau Provincial Park. A primary limiting factor for these turtle species is reproductive success. Critical nesting areas are threatened by anthropogenic disturbance – recreation, development, vandalism, erosion, etc. Human recreation (boating, swimming, walking, etc.) is common on or near the nesting beach at Rondeau. These threats are compounded by a potentially high rate of embryo/hatchling mortality from predators, including flesh flies.
These threats are being assessed so that mitigation procedures can be comparatively tested in order to increase population growth and sustainability. The mitigation methods include the translocation of nests to large-scale predator exclosures, translocation of nests to random sites, scent dispersal at nest-sites and artificial incubation. Also, factors involved in turtle nest-site selection and the life-history of the species of flesh fly will be thoroughly examined.
Rondeau Provincial Park is experiencing nearly 100% depredation of all turtle nests within the project area. Although nesting activity is currently high, the adult turtles in these populations are likely old individuals; however, since recruitment (when a new sexually reproductive individual enters the population) is dependent on embryo hatch success and embryo hatch success is currently near or at 0%, the population will crash when these older turtles die. Therefore, completely assessing the threats and developing recovery actions must be completed in this relatively short period of time when large numbers of sexually reproductive turtles remain in these populations.
The positive impact on the recovery of these species is an increase in embryo hatch success. By increasing the hatch success of turtle eggs in this population, more hatchlings will enter the ecosystem and there will be a corresponding increase in the likelihood of successful recruitment. Data from this study will be used to inform recovery teams and this research will aid in the development of recovery initiatives.