By Carrie Flood
A snake? Really? YES REALLY.
See, it’s never “just a snake.” It’s an ecosystem, an interaction, a connection between living things. Think of all living things on earth as intersections on a giant orb web. As humans, we exert pressure or control on almost all living things, so we would be near the center of the web. We modify local environments to make them more habitable for humans, and we harvest resources, which has an effect on the rest of the species that share the planet.
MEANWHILE, animals are doing the same thing only much, MUCH slower. Each successive generation is better at getting food, hiding from predators, or utilizing some untapped resource. Over millennia, plants and animals have diversified to fill every possible niche. We call this phenomenon biodiversity. Abundant biodiversity is a sign of a healthy, intact ecosystem. Or, in this example, a giant orb web with lots of spokes. The more spokes on the web, the more stable the humans near the center are.
One of my favorite examples of this is specialized pollinators. Some orchid flowers have extra long corolla tubes (the part that holds the nectar,) which means that only moths with extra-long proboscises can pollinate them. Both the flower and the moth benefit from the specialization; the moths have a food source that no one else can reach, and the orchid is practically guaranteed to be pollinated in a habitat where there is fierce competition for the attention of a pollinator. Win-win!
The trouble with this system starts if that moth disappears. The orchid has no way to reproduce. The orchid may be the only home for a frog, which in turn could be an important food for a specific bird, and that bird can only nest in a particular species of tree, whose fruits are the main source of food for some little forest mouse, which is prey for a beautiful spotty jungle cat, which then disappears because there are no moths.
That is a huge oversimplification of a hypothetical situation, but you get the idea. Bottom line: It’s not “just a moth.” Eventually all those connections start to affect the humans near the center of the web.
And THAT is why the Phoenix Zoo works to save Louisiana pine snakes, one of the rarest snakes in North America. Louisiana pine snakes feed mainly on pocket gophers, which eat herbaceous plants that grow in the sandy soils and abundant sunlight available in mature, old-growth longleaf pine savannas of the Gulf coast. (See? It’s all connected…) Due to heavy logging near the turn of the last century, the mature longleaf pine savannas had largely disappeared by 1935. Newer stands of the pine trees were managed for harvest every 30-40 years, meaning the forest never matured into good habitat for the pine snakes. Not to mention the building of roads, which carried snake-squishing cars through the middle of the remaining prime habitat. Oh, and as if that weren’t enough, Louisiana pine snakes reproduce really, really slowly. So there’s that.
The first step in saving the Louisiana pine snake was securing protection for the snake and its habitat, which happened in March of 2004. Then someone had to figure out how to help the snakes make more snakes, and that’s where we came in. All of the pine snakes in AZA-Accredited facilities were inventoried and compiled into a studbook, which is managed by one of our very own curators here at the Phoenix Zoo. (One of the MANY benefits of being a member of the AZA is great cooperation with other zoos. We benefit from shared expertise and best practices of other facilities. It’s the zoo version of “It takes a village.” More on that in a future post.) Information on those animals was fed into a software program that generates breeding recommendations to maximize genetic diversity.
After the individual animals are in the right places with their scientifically chosen genetic match, then it’s time to sit back, relax and let nature do its thing. (And by that, I mean compulsively gather data on temperature, humidity, activity levels and behavior so that we can figure out what the snakes need to make more snakes.)
To date, nine of the 23 snakes hatched here have been released into protected areas in Louisiana. That’s not very many, but considering the challenges facing this snake, we’re pretty excited about our contribution to saving an entire species. The other 14 animals have been incorporated into the managed SSP breeding population to be able to produce more snakes for release. The SSP will begin releasing larger numbers back into Louisiana once the managed population becomes high enough to sustain a more large scale release program. It’s the start of a long recovery process for the Louisiana pine snake, which is so much more than “just a snake.”