Invasive Species Week – Invasives at the Zoo

June 10, 2020

In honor of Invasive Species Week, we would like to highlight some of Seneca Park Zoo’s Ambassador Animals. These animals join programs to help the Zoo tell the unique stories of their species.

Invasive species are plants or animal species that are not native to a location. They have been introduced to the area and often cause damage to that ecosystem.

A great example of an invasive that has wreaked havoc in areas around the world is the marine toad, also known as the cane toad.

Marine Toad

Marine toads have been described as “the most introduced amphibian in the world”. Originally from southern Texas down through northern South America, this species was introduced by humans for pest control into places that it normally wouldn’t be found, such as Puerto Rico, Haiti, Hawaii, Florida and Australia.

How can a little toad cause big problems in an ecosystem? In many ways.

Marine toads are highly toxic at all stages of their life – including when they are eggs. Each female marine toad can lay up to the massive amount of 40,000 eggs at a time. Toxic eggs, tadpoles, and adult toads cannot be eaten by predators. Predators in the marine toad’s natural range have adapted to dealing with the toxins, but predators in the introduced areas have not. This makes it so that nothing can control the marine toad population, and their numbers increase exponentially as they out-compete the native animals for resources. This causes harm to the native animal populations.

Marine Toad photo by Marie Kraus

Normally, amphibians find food by seeing movement – an insect crawling or flying by. Marine toads utilize their sense of smell instead, and will eat practically anything that smells good to them – plants, dead or live small animals, trash, pet food, etc. Since they will eat almost anything, food is never limited. This gives them a high chance of survival, helping their populations to boom.

At Seneca Park Zoo, we have marine toads Bubba and Gump. As Ambassador Animals, they join outreach programs as well as programs within the Zoo. Bubba and Gump are wonderful ambassadors, bringing the messaging of invasive species to our community.

New Caledonian Crested Gecko photo by Marie Kraus

New Caledonian Crested Gecko

Seneca Park Zoo has another Ambassador species that helps to tell the tale of invasives.  While New Caledonian crested geckos are not an invasive species, they have been greatly impacted by one – almost to the point of extinction. 

These geckos are only native to the island of New Caledonia, off of Australia.  They were thought to be extinct until 1994, when they were rediscovered.  What would cause an entire species to seemingly disappear and then come back from the brink of extinction? The little fire ant.

These ants were able to travel to the island of New Caledonia by latching onto human supplies such as boots and suitcases.  Enough of these invasive ants arrived in New Caledonia to create a viable invasive population.  

The fire ants prey on the geckos, with groups of ants stinging and attacking.  The ants also compete with the geckos for food by preying on the native insects.  The predation and competition were thought to have brought the geckos to extinction, until a few were found in select areas of the island in 1994.  

At Seneca Park Zoo, we have crested geckos Crazy Eye and Hopscotch, who are Ambassador Animals, just like Bubba and Gump.  Crazy Eye and Hopscotch are amazing animals, helping to educate our community on the impact of invasive species. 

Join us on our webpage and social media during Invasive Species Week to learn more about invasive species in our area, and how you can take action to help to lower their impact.

– Rhonda McDonald

*Banner photos by Elesa Kim (Marine Toad) & Wayne Smith (New Caledonian Crested Gecko)