Thanks to Dave and Janet for sending their presentations from the recent Bahamas
Natural History Conference. Really two talks in one, focusing on past and present
natural history. More detail on the information in the first part of the talk here.
After the jump, summaries from Dave and Janet on their presentations.
A Long-term Perspective on Plant and Animal Life in the Bahamas
David W. Steadman
Florida Museum of Natural History
Arizona State University
Extremely well preserved plant and animal fossils from blue holes in the Bahamas provide unparalleled evidence of environmental change over the past five or more thousand years. In particular, a diverse set of fossil plants, invertebrates, and vertebrates recovered recently from blue holes on Abaco portrays a unique prehistoric terrestrial ecosystem where an extinct species of tortoise was the top herbivore and the Cuban crocodile was the dominant predator. In our ongoing work we are studying how prehistoric and contemporary plant and animal communities respond to long-term environmental fluctuations, including human impacts following the arrival of Amerindians about 1000 years ago. This project is governed by two broad, related research questions. (1) What were the relative influences of climatic change vs. human impact in the northern Bahamas? We will use radiocarbon dated records of charcoal, pollen, plant macrofossils, and animal fossils to describe the changing plant and animal communities both before and after human arrival.
(2) What are the long-term impacts of contemporary land use on terrestrial biotic communities? We have surveyed forests and birds on Abaco over the last five years. We observed major differences in the resident and migratory (winter resident) bird communities that occupy the widespread Pineland on Abaco versus those in the much more restricted Coppice. We recorded 13 migratory species in Coppice (including at least three USFWS Species of Conservation Concern) vs. just six species in Pineland. Coppice sustains a more diverse set of migratory birds than Pineland. Coppice covers less than 10% of the land area of Abaco, and is the habitat-type most prone to loss and degradation through land development and human-set fires.
The project is funded by a US National Science Foundation grant to Steadman, Franklin and P. Fall, and we acknowledge support of Bahamas National Trust, Friends of the Environment, and The National Museum of the Bahamas / AMMC.