Thickened skin shedding from sluggish frogs and toads in patches, facing difficulties in breathing and feeding. A compromised immune system attacking and shutting down the body.
These are typical symptoms of chytridiomycosis, a deadly fungal infection known as an “epidermal epidemic” that has led to the disappearance of numerous amphibian species globally.
Although not yet identified in Manitoba, the disease might still be present in the province. Jackie Tran, a graduate student studying frogs and salamanders in southern Manitoba, stated that the pathogen is likely widespread across the continent and potentially in Manitoba due to reported occurrences.
Chytrid in frogs is caused by the fungal pathogen Batrachochytrium dendrobatidis; in salamanders, it is caused by Batrachochytrium salamandrivorans, believed to have originated in East Asia and causing significant population declines in European salamanders.
The disease has not yet crossed over to North America, according to current scientific knowledge. The origin of the frog and toad-infecting variety remains unclear, with suggestions that it may have emerged in Brazil and Asia before spreading globally, partly due to the exotic pet trade.
Chytrid has been directly linked to the extinction of at least 90 species and a decline in over 500 others, making it one of the most devastating infectious diseases among vertebrates. Its prevalence has been increasing in the U.S. and Canada in recent years.
Numerous Alberta frog populations tested positive for chytrid between 2006-2010, while studies in British Columbia found it in a portion of the sampled amphibians, particularly impacting northern leopard frogs. The leopard frog, historically found in Manitoba, has faced population declines across Canada, with suspicions that chytrid may have played a role in a significant decline in Manitoba’s numbers five decades ago.
Although chytrid has been confirmed in frogs in various regions, Manitoba remains chytrid-free officially, but researchers warn that this designation may be misleading. The disease has been confirmed in nearby provinces and territories, indicating a potential risk to Manitoba’s amphibians.
Tran’s research aims to proactively monitor amphibian populations in Manitoba for the deadly fungal pathogen to help prevent further declines. The project is part of a broader pathogen monitoring program initiated in the U.S.
The health of wetlands, crucial habitats for amphibians, is directly related to the well-being of various species and ecosystems. Monitoring and addressing threats like chytrid are essential to safeguarding amphibians and maintaining ecosystem health.
Results from ongoing experiments suggest that young leopard frogs can be inoculated against the effects of chytrid, offering hope for conservation efforts. Scaling up such treatments could lead to improved success in reintroduction programs and potentially aid in preserving vulnerable amphibian populations.
Tran emphasizes the importance of disease research in protecting wildlife and preventing further losses, highlighting the need for proactive conservation measures to secure the future of amphibians in Manitoba.