Wildlife Health
Hawaiian Islands Humpback Whale
Why is it a concern?
For “key” species in marine sanctuaries (e.g., keystone species, foundation species, indicator species, and other focal species), measures of condition and health can be important in determining the likelihood that these species will persist or recover and continue to provide vital ecosystem functions and services. Measures of health (condition) may include growth rates, fecundity, recruitment, age-specific survival, tissue contaminant levels, pathologies (disease incidence, tumors, deformities), injuries and the presence and abundance of critical symbionts or parasite loads.
Species such as humpback whales, dolphins, monk seals, seabirds, and corals provide important ecosystem functions and services and are considered “key” species within the sanctuary. Humpback whales are a focal species in the sanctuary and the current abundance of humpback whales is estimated to be approximately 10,000 breeding whales around the Hawaiian Islands. Currently, humpback whales remain listed as endangered under the Endangered Species Act. Major threats to whales include entanglement from marine debris and ship strikes.
Hawaiian spinner dolphins are common throughout the Hawaiian Archipelago and within sanctuary waters. Spinner dolphins move nearshore into bays and coves during the day to rest, care for their young, and avoid predators. During this time they are prone to human disturbance.
The Hawaiian monk seal (Monachus schauinslandi) is a critically endangered species that is endemic to the Hawaiian Islands. In total, the population is estimated to be only 1100-1200 individuals with a little over 10% of individuals inhabiting the populated Hawaiian Islands. The health of monk seals is monitored by researchers and major threats include entanglement in marine debris, effects from human interaction, vessel strikes, infectious disease, genetic effects of small population size, fitness loss due to food limitation, death by predators, and loss of habitat due to climate change.
While not always considered part of the ocean environment, seabirds are true marine organisms, as they are completely reliant on the sea for food and only come to land to breed. In the populated Hawaiian Islands, there are 22 species of breeding seabirds. Threats to Hawaiian seabirds include loss of nesting habitat, introduced predators, ingestion of and entanglement in marine debris and effects from human interaction. The Hawaiian petrel (Pterodroma sandwichensis) is listed as endangered and the Newell’s shearwater (Puffinus newelli) is listed as threatened.
Coral animals are an important component of Hawaiian coral reef ecosystems and provide the three-dimensional structure that provides habitat and nursery grounds for many species of fish, invertebrates, and marine algae. Threats to coral health include coral bleaching, coral disease, pollutants, and physical impacts such as damage from vessels or anchoring.
Overview of Research
Science Needs and Questions
- What is the chemical composition of healthy whale breath versus that from compromised whales?
- What visual characteristics can be used to rate a marine organisms health (e.g. body or skin condition, behavior, external parasite and fouling burden …etc)?
- What is the spatial extent and level of disease incidence in the sanctuary for “key” species?
- What mitigation options are available for diseased wildlife?
- Are there coral species or areas that appear to be either more susceptible or more resilient to disease or bleaching?
- What are the mechanisms by which diseases are spread?
- How widespread are bleaching events in the sanctuary?
Education and Outreach Material
More information on entanglement in HIHWNMS
References
Craig, A.S., L.M. Herman, A.A. Pack. 2001. Estimating residence times of humpback whales in Hawai‘i. Report to the Hawaiian Islands Humpback Whale National Marine Sanctuary Off of National Marine Sanctuaries, National Oceanic and Atmospheric Administration, U.S. Department of Commerce and Department of Land and Natural Resources, State of Hawai‘i.
Lammers, M.O., A.A. Pack, L. Davis. 2003. Historical evidence of whale/vessel collisions in Hawaiian waters (1975 – Present). Final technical report to the NOAA Hawaiian Islands Humpback Whale National Marine Sanctuary. Honolulu. 25pp.
Lyman, E. 2010. Large whale entanglement and contact reports 2009-2010 season summary Hawaiian Islands Humpback Whale National Marine Sanctuary.