Since 2012, the Toronto Zoo team and partners have collected Blanding’s Turtle eggs from wild populations across Ontario. Each year, approximately 10–150 eggs are collected and incubated ex-situ using standard protocols (available upon request). Blanding’s Turtles have temperature-dependent sex determination, and males are produced when the eggs are incubated at or below 28°C and females are produced at incubation temperatures above 30°C [37 , 38 ]. At the Toronto Zoo, eggs are incubated at 27.5°C and 29.5°C to yield a 1:1.5 male:female sex ratio. Annual hatching success at the Toronto Zoo has ranged from 72% to 100%.
Hatchlings are reared in groups for two years prior to release. A maximum of 15 hatchlings are housed in each Waterland black plastic tub (91 cm x 45 cm x 40 cm), with shallow water (20 cm) and artificial vegetation for one year. After a year, a maximum of 7 hatchlings are housed in each tub. The water temperature is maintained at 25–27˚C in the first year and 23–24˚C in the second year. A 180 L sump filter with a heater located below the tanks is used for water circulation. The filter is cleaned once a week and the water is changed three times a week. One end of the tub is elevated and lined with rocks and pebbles, and a 50W bulb provides a basking area with 28–35˚C. A ramp is placed to facilitate easy access to the basking area by hatchlings. Two fluorescent UVB bulbs with full-spectrum lighting are provided for proper bone growth. The headstarted turtles are fed three times a week at roughly 5% of the average body mass of the cohort. One-year old hatchlings are fed turtle gel and beef heart gel (gel diets are gelatine-based foods for aquatic species formulated by the Toronto Zoo), earthworms, and romaine lettuce. After a year, all turtles are supplemented with fish (smelt) and live crickets. As part of enrichment and to promote better foraging ability in the wild, turtles are given varied food sizes, live worms, and natural tree bark for cover.
A maximum of 60 turtles are reared in human care for two years at the Toronto Zoo and released in June each year. A month before their release, headstarted turtles are relocated to large outdoor tubs (173 cm x 120 cm x 58 cm) with shallow water (25 cm) and artificial vegetation. Each outdoor tub holds a maximum of 25 turtles, and the number of tubs used varies annually. The water temperature in outdoor tanks is maintained at 28°C. Each tub is equipped with a filter and a water pump to create a current. The outdoor holding area is secured using mesh and roof fencing. All headstarted turtles are weighed using an Ohaus CS-series scale to the nearest 0.1 g and measured monthly for two years using Belt-Art calipers to the nearest 0.1 mm. Standard body measurements are recorded including midline carapace length and width, midline plastron length and width, shell height, and body mass. Prior to release, turtles are individually marked with notches on the marginal scutes [39 ] and a subcutaneous PIT (passive integrated transponder) tag is inserted into the left hind leg.
Hatchlings are reared in groups for two years prior to release. A maximum of 15 hatchlings are housed in each Waterland black plastic tub (91 cm x 45 cm x 40 cm), with shallow water (20 cm) and artificial vegetation for one year. After a year, a maximum of 7 hatchlings are housed in each tub. The water temperature is maintained at 25–27˚C in the first year and 23–24˚C in the second year. A 180 L sump filter with a heater located below the tanks is used for water circulation. The filter is cleaned once a week and the water is changed three times a week. One end of the tub is elevated and lined with rocks and pebbles, and a 50W bulb provides a basking area with 28–35˚C. A ramp is placed to facilitate easy access to the basking area by hatchlings. Two fluorescent UVB bulbs with full-spectrum lighting are provided for proper bone growth. The headstarted turtles are fed three times a week at roughly 5% of the average body mass of the cohort. One-year old hatchlings are fed turtle gel and beef heart gel (gel diets are gelatine-based foods for aquatic species formulated by the Toronto Zoo), earthworms, and romaine lettuce. After a year, all turtles are supplemented with fish (smelt) and live crickets. As part of enrichment and to promote better foraging ability in the wild, turtles are given varied food sizes, live worms, and natural tree bark for cover.
A maximum of 60 turtles are reared in human care for two years at the Toronto Zoo and released in June each year. A month before their release, headstarted turtles are relocated to large outdoor tubs (173 cm x 120 cm x 58 cm) with shallow water (25 cm) and artificial vegetation. Each outdoor tub holds a maximum of 25 turtles, and the number of tubs used varies annually. The water temperature in outdoor tanks is maintained at 28°C. Each tub is equipped with a filter and a water pump to create a current. The outdoor holding area is secured using mesh and roof fencing. All headstarted turtles are weighed using an Ohaus CS-series scale to the nearest 0.1 g and measured monthly for two years using Belt-Art calipers to the nearest 0.1 mm. Standard body measurements are recorded including midline carapace length and width, midline plastron length and width, shell height, and body mass. Prior to release, turtles are individually marked with notches on the marginal scutes [39 ] and a subcutaneous PIT (passive integrated transponder) tag is inserted into the left hind leg.
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