From the Archipelago: The No-Nonsense Porpoise

August-September 2001

This is an article from WaveLength Magazine, available in print in North America and globally on the web.
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by Alexandra Morton

I've spent a lot of time tracking salmon smolts this spring, documenting the explosion of sea lice in our area (see Failure to Protect), so I've become used to spotting the characteristic pattern of nested "V"s pink salmon smolts make traveling on the surface in search of insects and tiny planktonic organisms. One day as I was cruising around in my boat, I noticed a strange, single V-shaped ripple. Little salmon swim in groups of tens to hundreds, but this was a lone ripple. I idled my boat slowly closer. It isn't easy to glimpse wild freeswimming salmon because they are very tuned to predators from above such as kingfishers and blue herons.

As I got closer, I realized it was a tiny spider, water skiing! A tiny yellow spider had its two back legs braced apart and set delicately on the water's surface creating a pair of dimples. While the spider's back feet etched two slipstream wakes, its front legs were hanging on to the long arch of a single strand of web which reached into the sky. While the breeze was too minute for me to feel, it caught the spider's sail and this brave arachnid was on a voyage to new lands. You never know what you'll see in the waters of this earth.

Phocoena phocoena Graphic © Peter Folkens

While some events are rare and unique, others can be so common they aren't noticed. The surfacing of a harbour porpoise is like that. Harbour porpoise live closer to people on a regular basis than any other whale, dolphin or porpoise. This is not because they like us or benefit from our often sloppy ways, but because we both like the same habitat-shallow water, near land.

There are two kinds of porpoise resident to the coast of British Columbia, the Dall porpoise and the harbour porpoise, and they seem to have a pact which keeps them from competing with each other. The Dalls use the deep, more open waters, and the harbours stay closer to the beach. In the Broughton, Dalls are rare visitors in spring and fall, while harbour porpoise live right off the end of my float and throughout the narrow waterways of the Archipelago year round.

I remember a neighbour radioing me one time, "Alex, there's a new kind of dolphin just off my float house, you might want to come and take a look." I am always on the look out for the strange finless dolphin, the right whale dolphin, which travel with Pacific white-sided dolphins just off shore. I expect one day a few might wander in here with the white-sides, but to date I have never seen them follow their pod-mates inshore. So I dashed over expectantly, only to find the woman pointing excitedly at the harbour porpoise which had been living there for years.

There is something about these porpoise which simply slips beneath our radar, they are generally too understated for us to notice.I scan for them every morning as I wait for the water to boil for coffee. Their faint rapid breathing can only be heard on the calmest of mornings, but they are there most days throughout the spring, summer and fall.

Full-grown harbour porpoise reach about 5 feet and 100 pounds. They have a rounded triangular fin, with no hint of the sickle-shape characteristic to dolphins. They are a mousy-gray on top, white beneath and delicately streaked between the face and throat. We don't really know how long they live, some say 8 years, others 15, and still others suspect they live much longer.

I see newborns in June through August. They are tiny footballs shadowing their mother's every move. Baby cetaceans typically swim just behind the widest point of their mother's body, right behind the dorsal fin. Tucked in behind the outward curve of mom's ribs, the little ones surf a back eddy. I have seen baby dolphins with their eyes shut thus cradled by the flow of water along their mother's body. I salvaged a dead baby once and when I lifted it, it was no bigger than an average spring salmon.

Through the summer I see harbour porpoises in groups of two to three-Mom, her newborn and last year's baby form the core group. Often a much larger one tags along peripheral to the threesome. These, I think, are the males, waiting for the new mother to ovulate again.

Harbour porpoise eat small fish, including shiner perch, herring and perhaps capelin. In early winter, the porpoise become only sporadic visitors to my waterfront. Weeks go by without seeing the adorable little fins slicing along the tidelines they patrol. As I wander the archipelago in my boat, however, I find them here and there in much bigger groups of 10-30. At first,when I see so many fins, I think they must be the gregarious Pacific white-sided dolphins, but then when one turns broadside, the blunt, triangular profile of their fin reveals them as porpoise.

The guide books often say harbour porpoise don't jump, but they do. On very rare occasions I have encountered very active assemblages of these otherwise demure cetaceans and it is there I have glimpsed their blunt little faces airborne. Unlike the Dall porpoise, I have never known a harbour porpoise to bowride. They do have an odd habit of rising to the surface and exposing their back in a speedy, porpoising motion when a loud speedboat passes them. They look like they might intend to bowride, but are often pointing away from the boat. I think they may find these loud motors overwhelming and their quick darting movementsare more of a startle reaction.

One of the porpoise in my area has a bullet wound. As it rolls at the surface, a glimmer of light winks through a hole in its fin. Another has a nip mark out its fin. These marks make the tool of photo-identification possible, but in practice, they travel too erratic a route to sidle up to them and snap their portrait. I suspect the mother and youngster off my float everyday are the same individuals, but I don't know for sure.This is probably their foreshore, perhaps intheir family for years, decades or centuries.

When the pilchard returned for a brief period in the winter of 1997 after a 60 year absence, the porpoise didn't know what to do with them. For the first few months they tagged along behind the cylindrical 25cm fish rich in oil and much-needed calories. Then they began zooming through the schools, causing an eruption of fish to woosh airborne with the force and intensity of a blowing humpback whale. That spring I saw the only two cases of twin porpoise I haveobserved in 17 years of looking.

While harbour porpoise are declining around southern Vancouver Island, they are still abundant in the Broughton Archipelago and are a common meal for the mammaleating orca. When chased, the porpoise sometimes head for shallow water. The large male orca can't keep up or get close to them, seemingly burdened by their enormous dorsal and pectoral fins. But the smaller females and teenagers do keep pace with the porpoise.

I've seen them streaking along white clamshell beaches. Pfffft, pfffft, blow the porpoise, followed by the KWOOOOOOF of the whale. As they approach the end of the beach, the porpoise turn on a dime and head away from shore and, more often as not, are met by the male contingent of the orca family.

A kayak is the perfect vessel from which to observe harbour porpoise. Look along the tidelines of the narrow passes of the Archipelago. They are not shy, just no-nonsense and if you are lucky you might see them flash beneath your boat, for a split second, before they vanish again.



I hope some of you can join us in the community of Echo Bay for our music festival on August 11th. The afternoon and evening concert in the park at the head of Echo Bay is put on the Broughton Archipelago Stewardship Alliance. The Alliance is monitoring and trying to heal the creeks in this area so that they can produce salmon once again. The festival includes an area for tenting, a beautiful beach and a potluck dinner you can contribute to with food and/ or donations. The theme is salmon, the lifeblood of this coast. See you there.


© Alexandra Morton is a marine mammal scientist and writer in the Broughton Archipelago. Email: wildorca@island.net