Harboring Hope or "Conservation Isn't Just a Fluke"
The days were waxing shorter. Until recently, the seas were full of the clamor of many humpback whales emitting feeding calls, of their clash and splash when lunging upward to engulf shoals of anchovies, or launching their great bodies skyward and landing with a thundering roar. Now the nearshore waters were quieter. These noisy neighbors had succumbed to an irresistible siren-song: the instinct to mate and give birth. They were moving south, to the breeding grounds of Mexico and Central America. But another type of whale – for even porpoises and dolphins are considered whales - a cetacean one-ninth the humpbacks’ size, remained: the shy, diminutive harbor porpoise, Phocoena phocoena. They live year-round in coastal waters, often venturing into inlets and, yes, harbors. Our small whale “homies.”
PUFFING PIGS: Harbor porpoises live in Northern Hemisphere sub-arctic and temperate shallow waters. They measure up to 5.5 feet, with dark gray backs and pale undersides. Usually traveling in twos or threes, they may form larger groups when working a patch of baitfish like anchovy, herring, or sardines. Fisherfolk often see them surface suddenly, inhaling and exhaling sharply, their “chocolate-chip” -shaped dorsal fins piercing the surface, then abruptly disappearing. Thus, they earned the moniker, “puffing pig,” an unflattering but apt description of their behavior, sound and form.
THE “WHALES IN THE ‘HOOD”: Our local subpopulation, the San Francisco-Russian River stock, ranges from the Bay Area north to Point Arena. NOAA’s latest population estimate is 9,886, and appears stable. They were hit hard by fisheries entanglements in the 1970s and 1980s until restriction of gill nets to deeper offshore waters significantly reduced drownings.
Dating back to when Ohlone peoples fished for them inside the San Francisco Estuary, these shy, diminutive porpoises were likely common. The bay was clean, and prey was plentiful. The Ohlones took just what they needed. But much later, the entrance to the estuary was discovered, and exploitative new “landlords” from colonial Mexico and New England sailed in. Gradually at first, then, with the Gold Rush, a tidal wave of humanity engulfed San Francisco Bay and its environs. The estuary’s health suffered, from placer mining, urbanization and industrialization. Some porpoises remained, but their numbers probably declined as bay productivity declined. In a final coup de grace, World War II triggered a surge in bay-based shipbuilding, associated industry and vessel traffic, discharges and noise pollution. A barricade of explosive mines and submarine nets across the Golden Gate forced porpoises into outer coast waters, where they remained. Any relicts inside the bay seem to have disappeared.
RETURN OF THE NATIVE: The effects of military activities lingered for approximately 65 years. Around 2008, reports trickled in of porpoises east of the Golden Gate Bridge – unheard of! They had suddenly rediscovered the bay, now a bountiful and thriving ecosystem, thanks to the agencies and grass-roots efforts that helped restore its impaired health. A volunteer non-profit, Golden Gate Cetacean Research, began working with NOAA Fisheries, Greater Farallones National Marine Sanctuary, San Francisco State University and others to launch a formal study, and has now photo-identified over 700 individuals using the bay.
These porpoises remain vulnerable to nets and fishing traps, to water and noise pollution. However, it seems that harbor porpoises are back in our estuary to stay. "The past decade has seen a remarkable influx of cetaceans into San Francisco Bay," said Bill Keener, a marine biologist with Golden Gate Cetacean Research. "It began with the return of harbor porpoises, but now we also have resident bottlenose dolphins and humpback whales coming here to feed each spring and summer." Greater Farallones, Cordell Bank and the other West Coast national marine sanctuaries have had a hand in these happy developments, working with scientists, other agencies, and caring individuals. We are witnesses to these positive changes. We know that recovery can be achieved, even with seriously impacted marinelife, especially when we all take part.