By Ryan Rash
|Rainbow after a light rain with great frigatebirds and boobies flying overhead.|
In my previous post, I compared our life in quarantine now to what I experienced on Johnston Atoll, out in the middle of the Pacific Ocean where I worked on an invasive species control project through the U.S. Fish and Wildlife Service (USFWS) with a small crew of other volunteers. While quarantine sounds like a prison, I had a very different interaction with my time on the island. After the first month there, it began to feel like my new life was “normal” and by the end of my 6-month deployment it felt like I was being evicted from my home. While my last post covered more of the mental aspect of isolation, in this post I’ll cover our reason for being there and a little of the island’s background.
|Red-tailed Tropicbird with chick.|
I flew to Honolulu, Hawaii, in May of 2019. I met the 4 other crew members I’d be isolated with and we immediately got to work, going through basic training and gathering supplies for our 6-month deployment to Johnston Atoll National Wildlife Refuge. Johnston has a lengthy military history beginning in the early 1930s, wrought with nuclear radiation and harmful chemicals like agent orange. These have since been remediated, but sometime in the early 2000s (after the military left in 2004), yellow crazy ants (Anoplolepis gracilipes) infiltrated the island via driftwood—or more likely as incidental passengers on personal vessels hopping between the remote Pacific islands. The crazy ants quickly took over the island, and proved especially detrimental for the resident red-tailed tropicbirds (Phaethon rubricauda) that nest on the ground. The ants swarm both nesting tropicbirds and their chicks, spraying them with formic acid expelled through their acidopores. After being sprayed repeatedly in the eyes, they become blinded and eventually perish and are consumed by the ants.
|Sooty terns courting.|
In 2010, USFWS researchers discovered the infestation, created a treatment plan, and sent out the first Crazy Ant Strike Team (CAST). Ever since, there has been a crew of ~5 people on the island at all times (apart from hurricane evacuations). Thankfully, the pesticide treatment worked, and yellow crazy ants haven’t been detected since December of 2017. Extensive monitoring continues, however, in order to be completely sure of their eradication. The last step in deeming the island free from crazy ants is bringing scent dogs out to survey for their formic acid scent trail, as the ants could have possibly taken up residence in underground plumbing and electrical conduit. This will hopefully occur at the end of this year, but COVID-19 is making that a bit more uncertain.
|Hawaiian Short-eared owl checking out who's there.|
Johnston Atoll is the only landmass in over 800,000 square miles of ocean, and one of, if not the, most-isolated landmasses in the world, and thus a key nesting/stopover point for many bird species. At the time of discovery of the ant infestation, it was home to the largest red-tailed tropicbird colony in the world with over 5,000 active nests and a survey that was just conducted in March, doubled that with over 10,800 active nests! If everything goes to plan, the dogs won’t find anything, thus bolstering our confidence that the ants have been eradicated there.
ABOUT THE AUTHOR:
Ryan graduated from Tarleton State University with a B.S. in Wildlife, Sustainability & Ecosystem Science in 2017. He volunteered and worked in the Biodiversity Center's Ichthyology Collection from 2017 to 2019 assisting with fish surveys and curatorial work. He loves field biology and everything that comes with it, and looks forward to his next position, wherever it may be, after the lockdown.