| Summary | MPA Study migrating species |
|---|
| Project | SESMAD |
|---|
| Subtype | Natural Resource Unit |
|---|
| Sector | Marine protected areas |
|---|
| Biotic | Yes |
|---|
| Explanation | |
|---|
| Commons Aggregation | Population |
|---|
| Explanation | The California humpback whale is one of at least three separate populations of Megaptera novaeangliae found in the North Pacific. The International Whaling Commission (IWC) considers all the humpbacks in the North Pacific to be one stock (SIMoN 2015). |
|---|
| Commons Boundaries | Somewhat unclear boundaries (2) |
|---|
| Explanation | Humpback whales are migratory species, having the longest migration documented for any mammal (Stone et al. 1990). The California stock spends the winters in coastal Central America and Mexico and migrates to areas ranging from the coast of California to southern British Columbia in the summer and fall. Some have been known to migrate to Hawaii (Calambokidis et al. 2000). |
|---|
| Commons Indicator | ["Ecosystem health and/or biodiversity", "Status of highly migratory species"] |
|---|
| Explanation | Humpbacks are used as a focal species for integrated ecosystem assessments along with other species, and as an indicator for marine mammal species (Redfern et al. 2012). CSCAPE, the Collaborative Survey of Cetacean Abundance and the Pelagic Ecosystem is a National Marine Sanctuary program to assess populations and to characterize the pelagic ecosystem of the US West Coast used humpback whale populations. This occurred from 2005 to 2007. |
|---|
| Commons Unit Size | Large (4) |
|---|
| Explanation | Fully grown, the males average 13–14 meters (43–46 feet) long. Females are slightly 1 to 1.5 m longer than males (Chittleborough 1965). Body mass is typically between 25–30 metric tons (28–33 short tons), with larger whales weighing more than 40 metric tons (Burnie and Wilson 2005). |
|---|
| Environmental Medium | Oceanic |
|---|
| Explanation | Marine mammal |
|---|
| Inter Annual Predictability | Moderate (2) |
|---|
| Explanation | Whales are almost certain to pass through the Sanctuary every year, but the number of whales to do so is less certain. The time of year for humpbacks to exist in Sanctuary waters is expected, but sometimes migration is a little later or early (as was in 2014). |
|---|
| Intra Annual Predictability | Moderate (2) |
|---|
| Explanation | The time of year for humpbacks to exist in Sanctuary waters is expected (April to December), but sometimes migration is a little later or early (as was in 2014). |
|---|
| Commons Renewability | Renewable (1) |
|---|
| Explanation | Renewable but these species are slow to reproduce and have low regeneration rates. |
|---|
| Productivity | Poorly productive (1) |
|---|
| Explanation | Humpback whales mate at about 7 years of age. Females are pregnant for about 11 to 12 months and get pregnant approximately every two to four years (NOAA Fisheries, 2015). |
|---|
| Commons Accessibility | Somewhat accessible (2) |
|---|
| Explanation | Humpback whales can be found tracking birds if they are feeding, GPS tracking, and listening to sonar. Whale watching companies know common feeding and migration spots. |
|---|
| Commons Heterogeneity | High (3) |
|---|
| Explanation | While migration routes are somewhat known, finding a whale at any one point is not guaranteed and these are vast areas. |
|---|
| Commons Mobility | High (3) |
|---|
| Explanation | Humpback whales have the longest migration of any mammal. The stock found off the coast of the California sanctuaries travel to Mexico, Hawaii, and Central America. |
|---|
| Commons Spatial Extent | 395630 |
|---|
| Explanation | 115,200 nautical miles roughly according to Calambokidis et al. 2000. |
|---|
| Technical Substitute | No |
|---|
| Explanation | There is no technical substitute or technology that can take the place of humpback whales in the Sanctuaries from an ecological or economic standpoint. |
|---|
