Impact and threats |
level |
Evolution In the short term |
Evolution In the long term |
Species affected |
Habitats affected |
Description / comments |
Exploitation of natural ressources: Fishing |
very important |
unknown |
unknown |
Drastic declines in reef fish landings during the 1980s and 1990s lead to efforts to
reduce extraction and to restore reef fish populations in the Tortugas region. Several
regulations were enacted to limit the species targeted, gear types used, and daily
catches landed from the region (http://www.nps.gov;
http://floridakeys.noaa.gov/regs/welcome.html). In 1935, commercial extraction was
prohibited within the original Fort Jefferson National Monument and later in
DTNP. In 2001, commercial extraction also was prohibited within the wider
Tortugas Ecological Reserve outside the Park. More recently (2007), the
implementation of the RNA zone further prohibited recreational fishing in 46% of
the Park while allowing scuba diving, snorkeling and other nonextractive activities. |
|
Reef fish assemblages in the Dry Tortugas have suffered significant declines in the
abundance and size of desirable species because of historical overfishing. Although
full recovery is expected to take decades, the establishment of no-take reserves
coupled with a suite of management actions that reduced fishing mortality already
are having a net positive effect on previously exploited reef fish populations. Several
studies have characterized population abundance and size of exploited species and
are tracking their temporal trends to evaluate the effectiveness of no-take reserves,
including the newly established RNA within DTNP. Other anthropogenic stressors
including ocean warming and sea level rise are more difficult to quantify for their precise ecological impact. Monitoring of corals will yield information on trends in coral health. |
Exploitation of natural ressources: Agriculture |
limited |
unknown |
unknown |
|
|
N/A |
Exploitation of natural ressources: Tourism |
limited |
unknown |
unknown |
|
|
N/A |
Exploitation of natural ressources: Industry |
limited |
unknown |
unknown |
|
|
N/A |
Exploitation of natural ressources: Forest products |
limited |
unknown |
unknown |
|
|
N/A |
Increased population |
limited |
unknown |
unknown |
|
|
N/A |
Invasive alien species |
very important |
unknown |
unknown |
Lionfish have been observed in DTNP since 2010 and may cause direct impacts on
reef fish and invertebrates by predation, including ecologically and recreationally
important species. |
|
DTNP and National Park Service adopted a Lionfish Response Plan to
evaluate and mitigate the impacts of lionfish on DTNP resources. |
Pollution |
limited |
unknown |
unknown |
|
|
N/A |
Other |
significant |
unknown |
unknown |
- turtles
- colonizing seabirds |
|
Sea level rise and increased storm intensity is likely to inundate and erode the low-lying Tortugas islands over time thereby reducing the availability
of nesting beaches for sea turtles and colonizing seabirds. Anchoring can damage
corals and is addressed by the RNA zone where anchoring is restricted.
Unpredictable disturbances, including hurricanes, disease outbreaks, and coldwater
and warm-water events, and other extreme events have resulted in atypical
oceanographic conditions that have negatively affected reef-building corals and
seagrass communities. Coral bleaching and disease outbreaks have dramatically
reduced populations of staghorn and elkhorn corals. |