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Copyright © 2010 Ecostudies Institute-
| A nonprofit organization committed to ecological research and conservation |
| ECOSTUDIES INSTITUTE |
| ECOSTUDIES INSTITUTE |
| Contact Information: Ecostudies Institute P.O. Box 703 Mount Vernon, WA 98273 305-213-8829 ecostudies@ecoinst.org |
| A rare Bahama Swallow (Tachycineta bahamensis) perches above its nest in a Caribbean pine (Pinus caribaea) snag located in a stand of old-growth pines on Andros. Photo Copyright © 2010 Gary Slater. |
Covering roughly 6,000 square
km, Andros is the largest island -
actually, a group of islands split by
a network of tidal creeks and
bights - in the Bahamian
archipelago. Andros is also the
site of a large-scale
demonstration project funded by
the Global Environment Facility -
Integrating Watershed and
Coastal Areas Management
program (GEF-IWCAM), the goal
of which is to create a Land and
Sea Use Plan that will guide future
development on the island.
At the request of The Nature
Conservancy, which is supervising
the implementation of the project,
we conducted a rapid ecological
assessment of avian communities
and their habitats on Andros. Our
goal was to identify areas of
significant conservation value.
Although the avifauna of Andros is
poorly known, the island provides
critical habitat for several West
Indian Endemics, including
km, Andros is the largest island -
actually, a group of islands split by
a network of tidal creeks and
bights - in the Bahamian
archipelago. Andros is also the
site of a large-scale
demonstration project funded by
the Global Environment Facility -
Integrating Watershed and
Coastal Areas Management
program (GEF-IWCAM), the goal
of which is to create a Land and
Sea Use Plan that will guide future
development on the island.
At the request of The Nature
Conservancy, which is supervising
the implementation of the project,
we conducted a rapid ecological
assessment of avian communities
and their habitats on Andros. Our
goal was to identify areas of
significant conservation value.
Although the avifauna of Andros is
poorly known, the island provides
critical habitat for several West
Indian Endemics, including
Great Lizard Cuckoo, Bahama Mockingbird, Bahama Woodstar, Bahama Yellowthroat, and Bahama Swallow. Although the
human population on Andros is relatively low, habitat destruction and degradation from population growth and land-use
changes (e.g., clearing forest for agriculture) likely have had significant impacts on birds. A better understanding of the
distribution of birds on Andros may allow for future growth to proceed in a manner that minimizes impacts to the island's
unique avifauna.
One of the most biologically unique and important areas that we visited was on South Andros, where we found one of only a
handful of old-growth Caribbean pine forests remaining in the world. This forest, part of the pine-rockland ecosystem that
also occurs in south Florida and parts of Cuba, occurs on slightly elevated outcrops of bare limestone in the western half of
the island. Perhaps because of the difficulty in accessing the stand - it is several kilometers from the main highway, and
until recently reaching the stand would have required an arduous trek across dense coppice or extensive mangrove flats -
or perhaps because the environmental conditions are poor for tree growth, the stand that we visited, and several others
nearby, were never harvested. This is in stark contrast to the rest of the Bahamas, were nearly every other stand of pine
has been clearcut at least once since the early 1900s. Old-growth conditions have never been documented in Caribbean
pine stands, and are poorly known even in the closely related slash pine forests of south Florida. What we found was a
structurally complex and diverse forest stand, very unlike the simplified second-growth stands that we've studied in south
Florida and on Grand Bahama. The stand supported a rich assemblage of birds endemic to the pinelands, including
nesting Bahama Swallow, Bahama Yellowthroat, Pine Warbler, Hairy Woodpecker, and Blue-gray Gnatcatcher.
human population on Andros is relatively low, habitat destruction and degradation from population growth and land-use
changes (e.g., clearing forest for agriculture) likely have had significant impacts on birds. A better understanding of the
distribution of birds on Andros may allow for future growth to proceed in a manner that minimizes impacts to the island's
unique avifauna.
One of the most biologically unique and important areas that we visited was on South Andros, where we found one of only a
handful of old-growth Caribbean pine forests remaining in the world. This forest, part of the pine-rockland ecosystem that
also occurs in south Florida and parts of Cuba, occurs on slightly elevated outcrops of bare limestone in the western half of
the island. Perhaps because of the difficulty in accessing the stand - it is several kilometers from the main highway, and
until recently reaching the stand would have required an arduous trek across dense coppice or extensive mangrove flats -
or perhaps because the environmental conditions are poor for tree growth, the stand that we visited, and several others
nearby, were never harvested. This is in stark contrast to the rest of the Bahamas, were nearly every other stand of pine
has been clearcut at least once since the early 1900s. Old-growth conditions have never been documented in Caribbean
pine stands, and are poorly known even in the closely related slash pine forests of south Florida. What we found was a
structurally complex and diverse forest stand, very unlike the simplified second-growth stands that we've studied in south
Florida and on Grand Bahama. The stand supported a rich assemblage of birds endemic to the pinelands, including
nesting Bahama Swallow, Bahama Yellowthroat, Pine Warbler, Hairy Woodpecker, and Blue-gray Gnatcatcher.
As exciting as it was to see an intact
assemblage of pineland birds, we suspect
that this old-growth stand, and the others
like it, support a hidden wealth of diversity
that we never saw. The stand supported
a remarkable degree of structural
complexity, for example large woody
debris, something we almost never see in
the pine rocklands of south Florida,
Grand Bahama, or even Abaco. It also
supported range of age classes of pine,
from seedlings to individuals with all of the
characteristics associated with age
(flat-topped, with thick, platy bark). In
other ecosystems, this "biocomplexity" is
often associated with high levels of
species richness. In other words, more
structurally and functionally complex
environments can support more species.
We hope to test this idea, and perhaps
reveal the hidden richness of an
ecosystem often referred to as a "barren",
by returning to this site with a group of
scientists who can help us conduct a
thorough taxonomic survey.
assemblage of pineland birds, we suspect
that this old-growth stand, and the others
like it, support a hidden wealth of diversity
that we never saw. The stand supported
a remarkable degree of structural
complexity, for example large woody
debris, something we almost never see in
the pine rocklands of south Florida,
Grand Bahama, or even Abaco. It also
supported range of age classes of pine,
from seedlings to individuals with all of the
characteristics associated with age
(flat-topped, with thick, platy bark). In
other ecosystems, this "biocomplexity" is
often associated with high levels of
species richness. In other words, more
structurally and functionally complex
environments can support more species.
We hope to test this idea, and perhaps
reveal the hidden richness of an
ecosystem often referred to as a "barren",
by returning to this site with a group of
scientists who can help us conduct a
thorough taxonomic survey.
| A large downed log - showing evidence of fire - in an old-growth stand of Caribbean pine on South Andros. The structural complexity visible in this photo is almost never apparent in stands that have been harvested. Photo Copyright © 2010 John Lloyd. |
However, any studies of these old-growth stands will need to occur soon, as plans call for the development of agricultural
fields in place of the pine rocklands (see: Andros Farm Road Gets Chamber Blessing). To that end, a new road has been
scraped through several miles of once-pristine tropical hardwood forest, ending just at the edge of the old-growth stand that
we visited.
fields in place of the pine rocklands (see: Andros Farm Road Gets Chamber Blessing). To that end, a new road has been
scraped through several miles of once-pristine tropical hardwood forest, ending just at the edge of the old-growth stand that
we visited.
| The new South Andros Farm Road cuts through several miles of previously unfragmented coppice. When completed, the road will provide access to a stand of old-growth pines, which will be plowed under to create farm fields. Similar efforts on other islands have failed due to the cost of the massive inputs of water and fertilizer required to grow crops on bare limestone. |
To learn more, you can read more about our
surveys on Andros in our report and you can see
a video about the old-growth pines at YouTube.
You can also read more press releases about the
farm road and the proposed agricultural
development in the old-growth pines: Andros farm
road gets Chamber blessing, Bahamas Agriculture
Corp. makes progress on Andros farm road, and
many others.
surveys on Andros in our report and you can see
a video about the old-growth pines at YouTube.
You can also read more press releases about the
farm road and the proposed agricultural
development in the old-growth pines: Andros farm
road gets Chamber blessing, Bahamas Agriculture
Corp. makes progress on Andros farm road, and
many others.
