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Intensification and western displacement of the North Atlantic Subtropical High (NASH) is projected for this century, which can decrease Caribbean and southeastern American rainfall on seasonal and annual timescales. However, additional hydroclimate records are needed from the northern Caribbean to understand the long-term behavior of the NASH, and better forecast its future behavior. Here we present a multi-proxy sinkhole lake reconstruction from a carbonate island that is proximal to the NASH (Abaco Island, The Bahamas). The reconstruction indicates the northern Bahamas experienced a drought from ∼3300 to ∼2500 Cal yrs BP, which coincides with evidence from other hydroclimate and oceanographic records (e.g., Africa, Caribbean, and South America) for a synchronous southern displacement of the Intertropical Convergence Zone and North Atlantic Hadley Cell. The specific cause of the hydroclimate change in the northeastern Caribbean region from ∼3300 to 2500 Cal yrs BP was probably coeval southern or western displacement of the NASH, which would have increased northeastern Caribbean exposure to subsiding air from higher altitudes.
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Tropical Kingbird at Staten Island, New York and a Northeastwards Surve of Vagrants to North America
Tropical Kingbird (Tyrannus melancholicus) is an abundant and widespread Neotropical species with an extended history of vagrancy to temperate North America (Pranty et al. 2016). One at Mount Loretto Unique Area, Staten Island, NY (40.503575, -74.218169) on 26 September 2021 was just the second for New York State, less than a year after the first, at Dobbs Ferry, Westchester County, 27-29 October 2020 (Tom Warren, Julien Ansellem, eBird). These New York records follow scores of records from Florida since 1982 and at least 25 from northeastern North America through 2020. Here we provide details for the Staten Island record, describe the broader recent increase in northward occurrence of vagrant Tropical Kingbirds, and address what could be responsible for this change. Specifically, we tested the hypothesis that the occurrence of Tropical Kingbirds in northeastern North America could be predicted by their occurrence in Florida and confirmed that this was so, supporting the notion that vagrancy to northeastern North America is the result of an ongoing process of population growth, exploratory behavior, and colonization.
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- Award ID(s):
- 2049303
- PAR ID:
- 10464824
- Date Published:
- Journal Name:
- The Kingbird
- Volume:
- 72
- Issue:
- 1
- ISSN:
- 0023-1606
- Page Range / eLocation ID:
- 2-8
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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