Update: 10 August 2011

by Sally Esposito on August 10, 2011

By: Susan White, Incident Commander

One of the many unique aspects of this project is the immediate and ongoing presence of people on the atoll after completion of baiting operations. Often-times when bait is applied to islands to remove rats, there are no people living there afterwards to see what happens right away. At Palmyra, however, there are people present year-round – managing, monitoring, and conducting research – so it’s possible they may observe things not seen on other projects. Targeted project monitoring will take place later this month and for the next two years and will be the arbiter of overall project success. But in the meantime, we have a wealth of direct, short-term feedback and observations to report.

One of the first notable observations was a lone, juvenile rat caught alive in camp on Cooper Island on July 10. The rat perished within a few hours and a necropsy showed some signs that the rat may have been exposed to bait. The rat was found within the time-window when we expected juvenile rats may emerge, and it was found in a transition zone between areas that were aerially and hand broadcast baited. Our operations team sought and received authorization from the EPA for a “detection response” bait application. The detection response baiting focused on the camp and a buffer area, and included hand broadcasting, refreshing bait stations, deployment of traps, and canopy baiting. This follow-up work is consistent with the Operational Plan and is outlined in the Environmental Impact Statement.

Team members from Island Conservation will return to Palmyra in mid-August to begin post-application rat detection and monitoring throughout the atoll. In the interim, FWS and TNC team members have deployed and regularly inspect detection devices (e.g., chew blocks) around the atoll. Staff and visiting scientists are also on the look-out for rat signs. No additional rats or rat signs have been detected.

Another notable observation is the increased size and scope of the sooty tern colonies. In past years, nests along the edge of the colonies were raided by rats and the colonies would visibly shrink during breeding season. This year, the colonies are larger and host more breeding sooty terns there than in past years.

Staff also report:
- Intact coconuts all over the place, as well as crabs actually eating coconuts!
- Large numbers of katydids, dragonflies, and snails, and more, or more obvious, juvenile land crabs.
- Young plant seedlings carpeting the forest floor.
- Ground nesting wedge-tailed shearwaters heard at night. These birds have not successfully nested at Palmyra in years, as they are extremely vulnerable to rat predation.

The team continues to look for evidence of unintended negative effects to the atoll from the bait application and will collect any shorebird carcasses found. None have been found since the baiting was completed, but if they are, they will be sent to the U.S. Department of Agriculture’s National Wildlife Research Center for analysis. These observations and collections will continue throughout the rest of the year.

The captive shorebirds and geckos all remained healthy throughout the project. The geckos were safely released back to their respective islands in early July. The shorebirds remained healthy and some even gained weight in captivity. The shore birds were released as a group on August 4th. Birds walked to a nearby puddle where they bathed and then flew north towards several “wild” shore birds. Each bird has unique leg banding numbers which will allow biologists and birders to identify them around the atoll and beyond. A FWS staff member observed four of the tagged birds flying together after they were released.

The domestic animals, Dadu the dog and Duchess and Tigger the two cats, continue to be closely monitored and remain in good health for their age. The cats live in a cabin and show no signs of ever wanting to leave it, though they are now free to go. Dadu remained on leash in camp, with occasional runs at North Beach, until August 6th, when his leash was removed. Team members on the atoll tell us he is very very happy to be off-leash.

We continue to be incredibly proud that the implementation of this complex project was completed safely and effectively, and are thrilled about the positive, preliminary observations of ecosystem recovery. Check back periodically here for more updates as time passes.

Bristle-thighed Curlew release. Photo: USGS/R.L. Breeden

Sooty Tern colony on Palmyra Atoll. Photo: Island Conservation/E. Oberg

Sooty Tern with egg on Palmyra. Photo: Island Conservation/E. Oberg

Cardisoma carnifex crabs. Photo: Island Conservation/E. Oberg

Eastern Island. Photo: Island Conservation/E. Oberg

Rare Pisonia Forest on Palmyra Atoll. Photo: Island Conservation/E. Oberg

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