Long-term avian monitoring as an environmental indicator for climate change


Nigel Ogle is an environmental and social scientist from Melbourne, Australia. Having just completed his undergraduate degree, Nigel hopes to learn more about the dynamic relationships between marine mammals and environmental processes, such as the effects of tidal oscillations, upwelling, nutrient availability, and climate change on whale population distributions. Nigel’s long-term career aspiration is to complete a post-doctorate and work in the field of marine mammal research in Polar Regions.

 

Having just completed a bachelor’s degree in Social Science (Environmental Society) and Environmental Science from RMIT in Melbourne, Australia, my arrival to the Alaska Whale Foundation’s Center for Coastal Conservation in Warm Springs Bay was probably the most abrupt yet incredibly perfect way to transition from University textbooks to frontier science. I recall utilizing every possible opportunity during my studies to write about the cetaceans in the North Pacific, so to witness these creatures firsthand and to participate with organizations, such as AWF, that are on the forefront of scientific research in this field, has been incredible.  

Our arrival to Warm Springs Bay was welcomed by the presence of a local humpback whale, Hobo, who greeted us by showing us her fluke just in front of the research center. Fortunately for us, she stayed within the bay for several more days bubble net feeding, which allowed us to obtain some data on this interesting behavior.

In addition to whale research, the Center for Coastal Conservation also has several other research projects underway, such as a long-term avian acoustic monitoring program to study local avian ecology. This monitoring program will allow us to determine not only the presence or absence of bird species to specific habitats but also the timing of arrival, population density estimates and more broadly, climate change. Arrival and departure times of certain migratory bird species can be used as environmental indicators (an ecological approach to measuring the degree of environmental change in a particular habitat). For example, if we find that certain bird species are arriving earlier than usual, these earlier arrivals could be indicative of warming annual temperatures. So far we have installed two acoustic devices in both muskeg and forest habitats and have been recording bird songs on specific time intervals centered on sunrise and sunset. 

The Varied Thrush (Ixoreus naevius) is a beautifully colored bird that generally lives in forest habitats containing large spruce, fir, and hemlock trees near coastal environments. When looking at the acoustic details of the Varied Thrush, its unique song often appears rather simplistic and much longer than most other birds on the spectrogram, making it relatively straightforward to detect among all the other sounds of the wild. The thick band of acoustic recording observed along the bottom of the spectrogram image below, for example, could be a combination of several other natural sounds, such as other songbirds in the distance, tree branches blowing in the wind, or the sound of roaring waterfalls spewing fresh winter snow-melt from the mountaintops.

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