Thursday, June 1, 2017

American Burying Beetle

The Wilds Ohio
This past Friday I ventured up to The Wilds in Muskingum County, Ohio, with the wildlife biologist for the Wayne National Forest and another wildlife intern for the National Forest. The Wilds is a fantastic wildlife conservation center that is known for offering open air bus tours through pastures containing rhinos, giraffes, Sichuan Takins, and a whole host of other exotic and endangered species. Our trip wasn't for these large and well-known species, though. Our trip was for a beetle... 

American Burying Beetle in Ohio
Meet the American Burying Beetle (Nicrophorus americanus). This 1.5 inch long orange and black insect is a very special species. It once ranged all across the eastern United States, from the Great Plains to the Atlantic Coast. However, over the course of the 20th Century the American Burying Beetle all but disappeared from the world. Population after population began dying out, prompting the government to list this species as Federally Endangered in 1989. The reason for the decline and near-extinction of the American Burying Beetle has been a mystery for decades, as no one has been able to unequivocally pin down the exact cause. Regardless of the reason why, the American Burying Beetle was in dire trouble. Zoos and other conservation centers around the United States began collecting what little natural populations remained in the northern Great Plains and other scattered regions in order to create captive breeding populations.

This brings us to The Wilds, which began captive breeding its own population of American Burying Beetles in 2007. Every year the conservationists at The Wilds take a portion of their captive population and reintroduces those beetles back into the wild at a location on their property. I was able to participate in the 2017 "Planting of the Beetles" and document the process.

American Burying Beetle Reintroduction
The American Burying Beetle has a rather interesting and unusual reproductive method. A pair will search for a fresh animal carcass—typically something between the size of a mouse and a pigeon. Upon finding a suitable carcass, the pair will begin to bury it to a typical depth of 4-10 inches. Once buried, the beetles will alter the shape of the carcass and add chemical secretions to it which will slow down the rate of decomposition. After this, the female will lay eggs in a separate chamber above the carcass. After the eggs hatch, both the male and female will use the carcass to feed the larvae. Once the larvae are ready to pupate, the parents will leave the nest.

American Burying Beetle Reintroduction Efforts
The whole point of this reintroduction day is for us humans to do all the hard work for the beetles about to be reintroduced. About two dozen volunteers from various agencies and organizations ventured into the forest and began digging lots of holes—110 to be exact. Once the holes were dug, each was then "seeded" with a dead rat.

Dan Beetem Director of Animal Management for The Wilds
Dan Beetem, the Director of Animal Management for The Wilds, examines a pair of American Burying Beetles.
After each hole was dug and seeded with a rat, the fun part began. Two coolers were stocked with dozens and dozens of tiny plastic containers, each containing a male and female beetle, with a few containing some "single" females.

American Burying Beetle Conservation
The volunteers would grab a container, pick an available hole, and then carefully add the pair of beetles into the hole. By completing the first half of the beetles' work, the conservationists aim to give this new population a leg up. The hope is that the beetle pair will realize that there is an appropriate food source that's already buried, and will then decide to mate with each other and give rise to the next generation.

American Burying Beetle Nicrophorus americanus
I first learned about the American Burying Beetle several years ago, and I've wanted to see one since then. I honestly thought I would never get to see one, but then I found myself getting to hold one. Moments like these—interacting with such a special creature on such a personal level—are what captivate and inspire me. These are the moments I hoped to experience when I chose to venture down the wildlife biology path.

American Burying Beetle Reproduction
When it comes to Ohio, there are several other organizations that have either previously reintroduced, or are continuing to reintroduce, populations of American Burying Beetles across the state. Whether these efforts have been successful in establishing a self-sustaining population is yet to be seen, however. An American Burying Beetle only lives for a year. For a self-sustaining population to be created, enough of the reintroduced individuals have to mate and lay eggs. Enough of these eggs must hatch and enough of the larvae must be adequately cared for. Enough of these larvae must then successfully pupate and overwinter. Enough of these overwintering individuals must then emerge, find a mate, find a carcass, and successfully reproduce. There are many steps in which something can go wrong, and most times all traces of a given reintroduced population vanish by the next summer. Take for example the efforts by the Cincinnati Zoo. Between 2013 and 2016, the Cincinnati Zoo released a total 748 adults into a park. These 748 adults were estimated to have produced a total of 2349 larvae. Each year, zoo workers would attempt to find any new adults in the area which were from last year's efforts. They only ever found 2 adults. It's possible that many new adults survived and then simply dispersed to other areas and were consequently never captured. It's also possible that most of the reproductive efforts failed at some point.

Reintroduction of the American Burying Beetle at The Wilds
Dan Beetem, the Director of Animal Management for The Wilds, looks on the American Burying Beetles' new homes with optimism.
You might be thinking that it seems like we're fighting a losing battle when it comes to reestablishing the American Burying Beetle. Maybe that's true; there have been more losses in the world of wildlife conservation than there have been successes. But when it comes down to it, the species is still extant. There is still a chance. Conservationists will continue their struggle to help this species survive. I hope to see a day where self-sustaining populations of the American Burying Beetle dot the landscape they once inhabited. It's too early to say whether this dream is realistic or not, but I will remain hopeful.

1 comment:

  1. Trying to remember when I first learned about burying beetles. Glad to hear researchers are still working to save it.