8 March 2012

Claudia, the refuge biologist, is on FMLA and is only working weekends and Mike Evans, refuge manager, is off-island doing firearms training, so we connected with Toby Hairston to get our traps and equipment from the refuge this morning. Toby works in Wildlife Services for the USDA and is on contract to the USFWS and other agencies to control nuisance wildlife, including mongoose engaged in turtle nest predation. Toby has been here for several years and is fun to talk with about wildlife biology and government bureaucracies. A major topic of conversation today was the new refuge road. The US Department of Transportation designed and built the new road that changed the entire character of the refuge. They straightened out parts of the road and made it wider, but more importantly they graded it and added several feet of crushed rock to make a nice flat surface. There used to be sections of the road that were impassable to passenger cars and high-clearance vehicles could only travel at speeds less than 5 MPH. A trip that once required 30+ minutes to complete is now a mere 5 minutes, making the refuge appear much smaller. Making the refuge more accessible is a good thing. Unfortunately, the refuge budget does not include funding for maintenance. The road was completed last September and it is starting to develop a washboard contour in many places and the vegetation is rapidly closing in on the shoulders. We used to say that driving the old road was good for removing barnacles from your vehicle (and making the rental car companies upset). The new road will return to that status by this summer. It kind of reminds me of the state funding we received to build a new field house/physical education complex. A beautiful new facility was built but there was no money to hire maintainers for the building.

Our traps (N=21) are set and now we wait. I have not yet seen my first mongoose, but I know they are here. My memory, as feeble and unreliable as it is, is telling me that I always see at least one mongoose running across the road before we actually trap any. However, because I don't record those kind of events I have no idea how accurate this supposition is. In fact, after considering the supposition, I doubt its validity. I have read several studies that have demonstrated that we remember what want to remember not necessarily what we have observed. That is why data are so important to us scientists. I accept the oft-heard expression that data don't lie knowing that there is often more than one interpretation of the same data. For example, some who observe mongoose tracks at a sea turtle nest will argue that those data are evidence that mongoose are excavating nests and eating eggs and/or hatchlings. My interpretation of that same observation is that mongoose were at the nest site. I also don't accept that observation as evidence that mongoose are a major threat to sea turtles. However, I also understand that hawksbill and green sea turtles are endangered species and need protection, and their nests are close enough to the surface that mongoose could easily excavate them. Hatchling sea turtles are "supposed" to emerge from their nests after dark to reduce predation by birds and other diurnal predators, but some turtles forgot to read that memo. I also have trail camera images that indicate mongoose are active after dark on the refuge. So, to protect the sea turtles these exotic little animals need to be controlled. The question then becomes how best to control mongoose near nest sites. Currently USFWS personnel are condcuting removal trapping which is very labor intensive. Our data indicate that erecting barriers to prevent mongoose from moving onto the refuge would be a more efficient control method.