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Provides access to all site resources, with the option to search by species common and scientific names. Resources can be filtered by Subject, Resource Type, Location, or Source. Search Help
Researchers from Dickinson College and the U.S. Geological Survey collaborated on field research to understand the ability of human searchers to detect the invasive brown treesnake (BTS) on the island of Guam. Due to their nocturnal and tree-dwelling habits, these snakes are extremely difficult to detect, especially when they are present at low densities in an area. A new study "Use of visual surveys and radiotelemetry reveals sources of detection bias for a cryptic snake at low densities" published in the journal Ecosphere, helps explain why and provides valuable information on optimizing search methods and search locations that could be valuable if the BTS was accidentally introduced to a snake-free island.
The callery pear (bradford pear) is native is East Asia and was imported to the U.S. in 1908 and first sold commercially in 1961. Callery pear trees forms dense thorny thickets, produces flowers with an offensive odor, and produces large amounts of fruit that litter sidewalks. Additionally, the ‘Bradford’ cultivar is extremely susceptible to damage from storms due to branches having narrow crotch angles; these trees will also split under their own weight after 15-20 years of growth.