Islands are critical areas for biological conservation because they house a disproportional amount of the world’s biodiversity. However, island ecosystems are globally imperiled due to threats posed by invasive mammal introductions. Invasive house mice (Mus musculus) have ecosystem-altering ramifications on islands upon introduction through depredation of seeds, plants, invertebrates, and even seabirds. Mice impact island species’ distributions, densities, and persistence which in turn alters or disrupts nutrient cycles, symbioses between species, and other ecological processes. Mice can be eradicated from islands, but a critical uncertainty remains regarding island ecosystem response to such conservation interventions. This information is essential because it allows for novel questions about the direct and indirect impacts of mice to be tested.
|
Mouse Aggression on Midway Atoll National Wildlife Refuge
In December 2015, U.S. Fish and Wildlife Service biologists and volunteers discovered house mice attacking adult nesting Laysan and Black-footed Albatrosses at Midway Atoll National Wildlife Refuge, part of Papahānaumokuākea Marine National Monument. Mice attacks have been documented at other islands and on other seabirds, but never at Midway Atoll NWR on the adult, incubating albatrosses. House mice are not native to Midway Atoll and were inadvertently introduced to the atoll decades ago. Curiously enough, mice have coexisted among millions of seabirds nesting on the ground, in burrows, and in trees at Midway without obvious conflict--until now. Working with Island Conservation, USFWS is proposing to protect seabirds on Midway Atoll NWR by completely removing the invasive house mouse from the atoll, which is necessary to protect the largest albatross colony in the world as well as 29 other species of birds that rely on this unique Refuge. For more information on this proposed eradication, read through the Midway Seabird Protection Project Draft Environmental Assessment above. Collaborating with USFWS and Island Conservation, my graduate work will focus on the broader ecological monitoring of the mouse eradication on Midway Atoll NWR and quantifying the impacts of mice pre-/post-eradication on island flora and fauna. I am completing my PhD at the University of Tennessee's Ecology & Evolutionary Biology Department under the direction and guidance of Dr. Daniel Simberloff.
Midway Atoll NWR House Mouse Eradication Ecological Monitoring
Project Overview Collaborating on ecological monitoring since 2017 with the U.S. Fish and Wildlife Service and Island Conservation, we seek to understand the broader impacts on invasive house mice on Midway Atoll's flora and fauna. Monitoring activities include mouse diet analysis, arthropod community composition and diversity, as well as seabird demography.
|
House Mouse Diet Analysis What do house mice consume on Midway Atoll NWR? We will use eDNA metabarcoding/NGS combined with stable isotope analysis to ascertain mouse diet throughout different seasons and consequently use that data to inform ecological studies and ongoing monitoring to determine the direct and indirect ecological impacts of invasive mice on the Refuge.
|
Arthropod Communities Although mice are omnivorous they can also be very selective and may prefer invertebrate prey. On islands, mice tend to exhibit a preference for invertebrates that are slow-moving and relatively large. On Midway Atoll NWR, we hypothesize that mice likely prey upon large, ground-dwelling insects, such as Blattaria (cockroaches) and Coleoptera (beetles).
|
Follow Us!Check out our National Geographic Field Notes page for the latest updates on research and ecological monitoring out on Midway Atoll NWR!
|