Mayday Monday – What is Critical Habitat?

CLICK HERE for this week’s special feature, an interview with WDC’s Erich Hoyt, Research Fellow and Program Lead for Critical Habitat and Marine Protected Areas.

The National Marine Fisheries Service (NMFS) is the branch of the National Oceanic and Atmospheric Administration responsible for legal protection of marine life and the recovery of protected species. The Southern Resident orcas were added to the Endangered Species List in 2005 after NMFS realized that the population was in danger of extinction. While all orcas are still considered to be one species, Orcinus orca, there are ten known ecotypes, and very likely more, that are ecologically unique. Each ecotype is further divided into unique populations that are typically genetically and acoustically separate. For this reason, the Southern Residents are considered a Distinct Population Segment. 

The Endangered Species Act mandates that NMFS assign critical habitat for listed species or populations. Critical habitat is a set of legally designated areas that are directly or indirectly necessary to conservation, based on the presence of certain biological or physical elements. These can be within or outside of the geographic range of the population in question. Critical habitat serves as a legal acknowledgement of environmental properties that are necessary to survival and long term recovery. NMFS can manage activities within these areas to prevent harm to the whales, or damage to the environmental features they depend on.

For the Southern Residents, NMFS identified water quality, availability of prey species, and conditions for travel, resting and foraging as key environmental features. The current critical habitat includes about 2,560 square miles around the San Juan Islands, the Strait of Juan de Fuca and Puget Sound. Combined with Canada’s designated critical habitat, this covers the inland waters of the Salish Sea, where the Southern Residents are commonly seen from May to October. This does not include offshore areas, military sites or coastal waters less than 20ft deep.

In order to designate critical habitat, federal agencies must clearly identify the physical and biological features necessary for individual survival and population growth. By fully understanding what aspects of the environment are essential, the agency can better manage human activity in a way that does the least harm to these features.

Critical habitat is not the same as a marine protected area, but can be just as influential in long-term conservation. It is important to note that critical habitat designation does not directly safeguard a habitat as a whole the way a marine sanctuary does. It stands alone as an invaluable legal tool to prevent further damage to, and make a case for restoration of, essential environmental features. Its purpose is to create a legal means of protecting elements of the environment that are crucial to the day-to-day survival of individuals in order to first prevent further decline, and ultimately to promote population recovery over time.

Studies show that species with designated critical habitat are at least twice as likely to recover as those without it, but this is only going to be the case for Southern Residents if their critical habitat is actually based on their year-round needs. As it stands now, the Southern Residents’ critical habitat covers only a fraction of their geographic range. During the winter months, they travel up and down the coast, as far as central California, using the coastal habitat and ecological resources. In addition to being exposed to pollution and boat traffic, they are threatened by a decrease in prey. Salmon numbers have declined throughout their entire range, all year long. Unfortunately, current critical habitat does not reflect this.

You can help us expand the Southern Residents’ critical habitat. Please sign our letter urging NMFS to protect the full extent of their home.

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