The western painted turtle is the largest subspecies of painted turtle, with a shell that can reach approximately 25 centimetres long. It has a smooth, flat black carapace with an intricate network of delicate faint markings. Its distinguishing feature is the brilliantly red/orange colored plastron with an elaborate dark figure branching intricately along the shell seams. The head, neck, legs, and tail have yellow stripes against black skin. They can be spotted basking on logs, rocks, and sandy banks in ponds, lakes, sloughs, and slow-moving streams with muddy bottoms and abundant vegetation.
Males are noticeably smaller than females and have longer, thicker tails and longer foreclaws, while females are larger, and have thinner tails that don’t extend beyond the shell edge. Both sexes share the striking coloration pattern.
Age of maturation is reached in 8 to 10 years for males and 12 to 15 years for females year and they can live well over 50 years in the wild. Mating occurs between March to May in shallow water, with males performing elaborate courtship displays using their elongated foreclaws. Females travel up to 150 metres overland from June to August to deposit up to 23 eggs in warm, well-drained sandy soil, often laying second clutches 1 to 2 weeks after the first. Eggs incubate for approximately 70 to 90 days, and hatchlings that complete development too late in the season remain dormant within their nests throughout winter, emerging only when spring warmth arrives. Temperature during incubation determines sex: temperatures above 29°C produce females, less than 27°C produce males, and intermediate temperatures produce mixed-sex cohorts.
Bien que la sous-espèce de la côte Pacifique ait été officiellement désignée comme En voie de disparition par le gouvernement fédéral et inscrites sur la liste rouge en Colombie-Britannique, il n'existe pas encore de stratégies de rétablissement officielles. Une stratégie de rétablissement fédérale devrait être publiée en 2016-2017, et une stratégie provinciale pour la Colombie-Britannique est actuellement en cours d'élaboration. Entre-temps, il est important de protéger et de restaurer l'habitat, de surveiller les populations et de relâcher des tortues élevées en captivité pour augmenter ces populations.
Dans les milieux humides de la vallée du Fraser en Colombie-Britannique, les tortues peintes de l'Ouest font face à de nombreux défis, surtout à l'état d'œufs et de tout petits nouveau-nés. Avec une abondance de prédateurs affamés et aucun soin parental une fois éclos, seules quelques jeunes tortues survivent jusqu'à l'âge adulte. Lorsqu'on ajoute l'activité humaine à l'équation, le taux de survie peut être si faible qu'une population devient non viable. Depuis 2012, nous travaillons à améliorer ces chances. En plus de protéger les nids, nous collectons les œufs dans des nids de tortues vulnérables, nous les incubons artificiellement et effectuons le démarrage en tête des nouveau-nés avant de les remettre en liberté dans la nature.
Nous travaillons à prévenir la disparition de la tortue peinte de l'Ouest en soutenant et en renforçant les populations sauvages en Colombie-Britannique, et en poursuivant l'étude de l'espèce.
En 2023, nous prévoyons :
Découvrez comment Conservation de la faune au Canada contribue à la sauvegarde des Les reptiles et amphibiens du Canada, y compris les tortues peintes de l'Ouest, et comment vous pouvez faire une différence.
Protect wetland habitats from pollution and drainage. Drive carefully in turtle habitat, especially May-August during nesting season when females cross roads. If you encounter a crossing turtle, help it across in the direction it was heading. Report road kill turtles to wildlife authorities, this data helps identify dangerous areas. Never remove turtles from the wild and never release pet turtles. Support habitat protection and restoration of native wetlands.
Q: Why are there so many western painted turtles basking together on one rock?
A: Painted turtles are highly social animals with little apparent territoriality. They gather to thermoregulate, basking raises body temperature for efficient digestion, movement, and reproduction. These communal basking sites also offer safety from predators.
Q: Can western painted turtles really survive without oxygen for months?
A: Yes, western painted turtles have extraordinary anoxia tolerance, adults can survive over 170 days without oxygen at 3°C by entering a metabolic coma, slowing heart rate, and relying on anaerobic metabolism. This allows them to survive buried in ice-covered ponds throughout winter without access to any oxygen.
Q: Why do females sometimes not complete nesting?
A: Nesting attempts fail when females encounter poor substrate conditions or disturbances. Some nesting sites have unsuitable soil that makes egg laying impossible. Others are interrupted by predators or other disturbances. Failed nesters eventually return to water without depositing eggs, representing wasted reproductive effort.
Q: How important is water temperature to their survival in Canada?
A: Critical. The western painted turtle’s range expansion limits are determined by three factors: the length of the active season (how many warm months are available), mean ambient temperature during egg incubation (must reach optimal temperatures to hatch), and possibly mean winter temperature (too severe cold kills them). Climate change is shifting these boundaries, potentially allowing northward range expansion.
