It’s officially spring! Cherry blossoms are a sure sign that spring has sprung in the Pacific Northwest. But for Pacific white-sided dolphins, spring means herring. Each spring, Pacific herring find their way to inlets and coastal areas to spawn, laying tens of thousands of eggs. This dramatic event attracts birds, sea lions, and dolphins. We were lucky enough to capture footage of Pacific white-sided dolphins working together to corral herring. Dolphins require a quiet ocean to both to find their prey and to avoid predators like killer whales. Stay tuned for the results of our investigation to assess which areas along the BC coast are quietest for dolphins. Hope you enjoy!
Today, President Barack Obama designated five new national monuments, including Cattle Point on San Juan Island in Washington state. This is exciting news, not only because Cattle Point is beautiful and has historic relevance, but because important feeding habitat of one of the most critically endangered marine mammal populations in the US is just off Cattle Point. Our past research shows that in summer, southern resident killer whales (or orcas) have preferred feeding hotspots just off Cattle Point.
Cattle Point lighthouse San Juan Island
In 2009, we published a paper mapping where the whales carry out various activities within their core summer habitat. The idea was to identify and prioritize important habitat and to propose a candidate Marine Protected Area (MPA) for the whales, especially their feeding habitat. Our previous work has revealed that feeding behavior is the activity state in which killer whales are most vulnerable to disturbance from boats. Although we can’t protect all of their summer habitat by closing it off to or reducing boat traffic, and neither would we want to, it seemed sensible to us that we could protected the most important parts. In this case, that leaves their feeding areas.
Candidate killer whale Marine Protected Area (MPA)
Our colleague Anna Hall has spent years studying these neat critters and is helping to identify how these two ecologically similar species share the waters of the Salish Sea, while avoiding competition and together with Anna and Arliss Winship, Rob published a paper trying to estimate how many porpoise are being caught in salmon gillnets.
Harbor porpoise. Photo credit: Olive Andrews
So, we’re pretty invested in these species.
Our latest research effort on porpoise is a bit of a stretch for us. In July 2009, our colleagues Line Kyhn and Jakob Tougaard visited from Denmark with some sophisticated recording equipment. Hardware issues have made it difficult to compare echolocation patterns of these two species before, but Line worked magic! Line’s found some compelling evidence that these two species can be told apart acoustically — at least if you can hear over 120 kHz. Check out her PhD thesis for this work, and for results on other dolphins and porpoise around the world.
This may sound esoteric, but there are two reasons it’s so exciting. First, it teaches us something new about the biology of the species — how they avoid overlap with each other, and how they try to avoid being heard by mammal-eating killer whales. Secondly, it guides real-world conservation efforts, so that passive acoustic monitoring programs can detect which of these species is present when visual surveys are not possible — in remote areas, or at night, or in rough weather. That will help us identify important habitats, and protect them, as human activities on the BC coast continue to grow. We hope to have a paper on this in a scientific journal in the coming year. We’ll keep you posted.
Grey whales are pretty neat. We were lucky enough to encounter two of them on Boxing Day. Their visit to inshore waters of British Columbia in December was a bit of a surprise. Grey whales are legendary for their migration, which is among the longest of any mammal. We’d expect to see grey whales in spring and fall as they make their annual trip between Mexico and Alaska. But it’s December, so we were surprised to find that these two were in front of our field cabin rather than in Mexico with the rest of their family.
It seems grey whales are full of surprises. Our colleague, Bruce Mate, at the Hatfield Marine Science Center at Oregon State University, has tagged several individuals from the highly endangered Eastern North Pacific grey whale population off Sakhalin Island in Russia. One whale, now known as Flex, traveled from Russia to the Oregon Coast when its satellite tag stopped signaling. In 2012, another whale called Varvara, traveled from Russia to Mexico in two months!
Have you seen Big Miracle with Drew Barrymore and John Krasinski? If you haven’t, you might want to check it out. Based on a true story, the movie tells the tale of three grey whales that became trapped in the ice off Barrow, Alaska.
Anyway, we felt pretty lucky to photograph these two whales and are sending our ID photos to colleagues to see whether we can find a match in their extensive catalogs. Unique markings on grey whales (the pigmentation patterns on the flukes and flanks (sides) of the whales, as well as the knuckles on the back) offer clues to help identify who the whales are and where else they’ve been. We’ll keep you posted on whether our colleagues find a match.
Meanwhile, we’re still hoping to find Pacific white-sided dolphins when the winds die down. We hope you’ve had a great holiday season, and we look forward to having a lot of results from our ocean noise and dolphin studies to report in 2013.
