The project lost one of its founders on 24 August 2019, when Mary Bomberger Brown died in Lincoln, Nebraska, after a long illness. Mary was involved in all aspects of field work for the first 25 years and was also responsible for all data entry and management during that time. After she left the research in 2007, she remained an active collaborator on papers that continued to result from the previously collected data. Her expertise on cliff swallows was extensive and will be greatly missed.
The 2019 field season ended on 16 August 2019, and was one of the longest in the history of the project. Cold and very wet weather throughout the Great Plains during May delayed nesting until early June, and also resulted in a mortality event in mid-May when some cliff swallows starved to death during a 4-day period of inclement weather, much like we saw in 2017 (see news entry below). Once nesting began, reproductive success was high across all colonies and virtually all laying dates. Swallows that attempted late nesting in July, which leads to nest failure most years, were successful this year, with many nests with young active until mid-August. Successful late nesting on this scale was unprecedented in the history of the project. We suspect that the very wet conditions in May and June led to unusually abundant food resources that allowed the late birds to be successful. Highly variable conditions such as these from year to year likely drive fluctuating selection in cliff swallows, and one of our main objectives at present is to understand how fluctuating conditions favor different colony sizes and laying dates.
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