In May 2016, I embarked on a 7 hour road trip to extreme Southern, Ontario. Here I would catch a ferry to the center of Lake Erie so I could reach Pelee Island. This is the largest of the Erie Islands, a chain of archipelagic islands in the lake. As I arrived weather conditions were cool, damp, and rainy. Perfect conditions as I had traveled here to observe the Small-mouthed Salamander (Ambystoma texanum), Canada’s rarest salamander species. In the whole of the country, this salamander only occurs on this one small island. It is listed Federally as an Endangered Species.
Even on the island, the Small-mouthed Salamander is under threat. According to Ontario Nature, on Pelee Island it has declined as a result of habitat loss and degradation. Even modest human disturbance or natural catastrophes can have a severe negative effect on species whose populations are small and localized.
Pelee Island’s Small-mouthed Salamanders are not only unique because of their scarcity but also their genetic make-up. Many of the Small-mouthed Salamanders on the island are polyploid forms, meaning they contain more than two paired sets of chromosomes, and are made-up of uneven mixtures of genes from multiple salamander species from the Ambystoma genus. These Small-mouthed polyploids (often referred to as intergrades or hybrids forms) are apparently very uncommon outside of the region. Fish Point Provincial Park states that Small-mouthed/Blue-Spotted hybrids are rare outside of Pelee Island.
During my recent trip I was fortunate to encounter Small-mouthed Salamanders from all over the island. Close to 50 individual salamanders were observed! This includes several observations from areas of the island that I had not previously seen salamanders (during my past trips). One of these locations was on the north side of the island where a historical breeding site use to exist, but sadly no longer remains.
As always, getting to observe this rare and unique amphibian in the wild was an exhilarating and fantastic experience!