Turtles: Difference between revisions
From coraldigest
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''' Threats ''' | ''' Threats ''' | ||
#Desired for flesh and shell | #Desired for flesh and shell<ref name="conserve"></ref | ||
#Fishing methods | #Fishing methods | ||
#*Bycatch | #*Bycatch | ||
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#*Lighting – discourages females from nesting on developed beaches | #*Lighting – discourages females from nesting on developed beaches | ||
#*Erosion and armoring – these have affected the available space for nesting | #*Erosion and armoring – these have affected the available space for nesting | ||
#*Use of turtle nesting habitat for leisure – discourages females from using that area for a nest – beach driving, furniture on beaches | #*Use of turtle nesting habitat for leisure – discourages females from using that area for a nest – beach driving, furniture on beaches <ref name="conserve"></ref | ||
#Climate change | #Climate change | ||
#Predators | #Predators | ||
#*Nests – raccoons, ants, and crabs | #*Nests – raccoons, ants, and crabs | ||
#*Hatchlings – birds, crabs | #*Hatchlings – birds, crabs | ||
#*Adults – occasional shark attacks | #*Adults – occasional shark attacks<ref name="conserve"></ref> | ||
''' Conservation Efforts ''' | ''' Conservation Efforts ''' | ||
#Hard to monitor the effectiveness of conservation efforts because only nests are being observed – no idea of whole population status due to wide range and limited ability to track populations aside from nesting | #Hard to monitor the effectiveness of conservation efforts because only nests are being observed – no idea of whole population status due to wide range and limited ability to track populations aside from nesting | ||
#US Endangered Species Act – prohibits hunting of sea turtles and reduces incidental losses from shrimp trawling and development | #US Endangered Species Act – prohibits hunting of sea turtles and reduces incidental losses from shrimp trawling and development <ref> http://dels.nas.edu/Report/Assessment-Turtle-Status/12889 </ref> | ||
#Turtle Excluder Devices – a grid of bars with an opening at either end of the net, catches larger animals and ejects them through the opening while still catching the smaller animals ie: shrimp | #Turtle Excluder Devices – a grid of bars with an opening at either end of the net, catches larger animals and ejects them through the opening while still catching the smaller animals ie: shrimp <ref name="conserve"> http://www.conserveturtles.org/seaturtleinformation.php?page=threats </ref> | ||
== References == | == References == | ||
<references/> | <references/> | ||
Revision as of 11:58, 24 February 2014
Sea Turtles
General
Evolution
Distribution
Behavior and Ecology
Habitat
- Fairly shallow waters inside reefs, bays, and inlets
- Attracted to abundance of marine grass and algae
- Nesting requires open beaches with minimal disturbance [1]
Life Cycle
- Nesting season varies, occurs nocturnally at 2,3,4 year intervals
- May lay as many as 9 clutches in a nesting season
- Clutches range from 75-200 eggs
- Incubation ranges from 45-75 days
- Temperature affects incubation range and sex of hatchlings
- Strong nesting fidelity – green sea turtles [1]
Orientation
Diet
- Hatchlings eat a variety of plants and animals
- Adults feed almost exclusively on sea-grasses and marine algae
Relationships with Humans
- Hunting history
- Hawksbill – endangered
- Green – endangered in FL and Mexico, threatened everywhere else
Importance in Ecosystems
- Maintaining healthy seagrass beds and coral reefs
- Increase productivity and nutrient content of seagrass bladeswhen grazing
- Decreasing supply of nitrogen
- Hawksbills especially play a key role in managing the diversity of coral reefs by limiting the growth of sponges
- Balancing marine food webs
- Facilitating nutrient cycling
Threats
- Desired for flesh and shellCite error: Closing
</ref>missing for<ref>tag
Conservation Efforts
- Hard to monitor the effectiveness of conservation efforts because only nests are being observed – no idea of whole population status due to wide range and limited ability to track populations aside from nesting
- US Endangered Species Act – prohibits hunting of sea turtles and reduces incidental losses from shrimp trawling and development [2]
- Turtle Excluder Devices – a grid of bars with an opening at either end of the net, catches larger animals and ejects them through the opening while still catching the smaller animals ie: shrimp [3]