Why Coral Rays?
- Its cousin, the Giant Manta Ray recently added to endagered list
- Lack of awareness
- A group member had previous experience studying rays from another class
A vulnerable status (VU) - High risk of endangerment in the wild.
- Intentional Fishing
- Accidental Fishing
- Other Various Anthropogenic Causes
Why Does Intentional Fishing Create a Threat to the Manta Ray?
- Both targeted and incidental fishing affects Manta species
- Killed and/or captured by harpooning, netting, trawling, etc.
- Very easy targets:
- Large size
- Slow swimmers
- Aggregative behavior
- Predictable habitat use
- Lack of human avoidance
- High value in international markets:
- Prized gill rakers
- For food/local products
http://s3.amazonaws.com/uts-us/vol1/bc158a0d6f46be5dfcab8e6b698f2eca_1445261552ace83f026671475cfde6ed.mp3How Does Accidental Fishing Play a Role?
- Large Scale Fishing Industries
- Bycatch of Small Netting Strategies
- Mooring line entanglement and boat strikes
How is Tourism Adversely Affecting Coral Rays?
- Alter Natural Behavior
- Reduce Access to Living and Feeding Habitats
- Increased Exposure to Humans and Boats
Other Anthropogenic Causes:
- Habitat degredation
- Climate change
- Pollution (oil spills)
- Ingestion of microplastics
- Natural Predation: primarily from sharks and killer whales
- Relatively low subpopulations, less than 1,000 indviduals
- Low Immigration and Emmigration
- Losses in population/genetic varability are difficult to recover from.
- Estimated Global Population Decline of 30%
- Local population decline can be as high as 80% in some areas.
- Seasonal Migration
- Large Migration Areas, over 400 kilometers
- Site Specific Breeding Grounds and Life Cycle Areas
- Commonly resides in tropical and subtropical waters of the Indian and Pacific Oceans
- Manta Rays show no territorial behavior
Current Conservation Acts
- United States: criminal penalties and administative fines for knowingly capturing and killing Manta rays
- Maldives: export ban on all ray species
- Phillipines: banned fishing of Manta rays
- Yap: MPA for Manta rays created sanctuary
- Australia: protected from fishing
Week 13 Group Project