Steller Sea Blog

Whales Share Phylogenetic Relationship with Dogs

During the Eocene, some 53 million years ago, the earth was home to a species of hoofed-mammals known as Pakicetids. Based on the anatomy of their fossil remains palaeontologists have established that Pakicetids looked somewhat like dogs with hoofed feet and long, thick tails. They are also believed to an early ancestor of whales based on the shape of their auditory bulla, a bone located in the inner ear. The shape of the ear region in Pakicetus is highly unusual and only resembles the skulls of whales. The feature is diagnostic for cetaceans and is found in no other species. The teeth of Pakicetus also resemble the teeth of fossil whales, being less like a dog’s incisors, with a serrated triangular shape, similar to a shark’s tooth, which is another link to more modern whales. Given their evolutionary relationship I found the article below to be rather interesting.

Poop Patrol
by Monique Keiran, Canadian Geographic

A Black Labrador named Tucker is helping researchers determine why orcas summering off southern Vancouver Island are dying off.

Tucker lends his nose to science by standing in a moving open-decked motorboat and sniffing the wind to detect orca scat floating on the surface of the Strait of Georgia and Haro Strait. His human colleagues, including Sam Wasser, director of the University of Washington’s Center for Conservation Biology, scoop up the greenish brown goo and later analyze its hormone levels.
“Killer whale scat doesn’t stay afloat long, and it’s about the same color as the water,” says Wasser, who uses dogs to study elephants, caribou, spotted owls and other at-risk species. “Without a dog, we’d have a hard time getting enough samples.”
Because Tucker can smell the poop from a long way off, the researchers needn’t crowd the whales. Preliminary analysis of hormones in the scat suggests that boat traffic stresses orcas.
The results from samples collected since 2006 also indicate the whales’ preference for chinook salmon may be causing them to starve. Stress hormones in the scat peak and thyroid hormones plummet from September through December, when the salmon are at their scarcest. Thyroid hormones help regulate metabolism. When the animal starves, levels drop and metabolism slows. Wasser says the hormone levels mirror observed orca death rates.
“In 2007, thyroid levels in the samples were highest, and no whales died. They were intermediate in 2006, when there was five percent mortality, and lowest in 2008, when mortality increased to eight percent.”
More samples are needed to confirm the results. Wasser and Tucker will return to the straits to patrol for poop this summer.

Filed under: orca | at-risk, evolution, orca, science, whales|No Comments

Congratulations Jack!

Recently a friend of mine returned from nearly two months in his kayak, as he paddled from Salt Spring Island to Skagway Alaska. I’ve seen some of his fantastic pictures and am eagerly awaiting the his narrated travelogue. In the meantime, however, here’s a brief article I copied from the Gulf Islands Driftwood.

Kayaker Completes Epic Voyage: 51-day trip covers 2,200 kilometers

by Sean McIntyre, Gulf Island Driftwood, Wednesday, June 10, 2009

When jack Rosen talks about going on a kayak expedition, he’s not fooling around. Rosen has taken on many challenges since starting up Island Escapades in Ganges 19 years ago.

His trips include paddles through world-class destinations like Patagonia, Belize and Haida Qwaii. But none of those compared to Rosen’s recent 2,200 kilometer journey from Ganges Harbour to Skagway Alaska.

“It was a phenomenal trip, and epic journey,” Rosen said last week, a few days after his return from the 51-day trip he and fellow paddler Brian Craig of Calgary began in April. In an interview before his departure, Rosen said the weather would prove the biggest factor for the pair’s journey. Short of a few days of stormy seas along the exposed Pacific Coast near Cape Caution north of Vancouver Island, the weather played a minor role. Given the team’s route through one of the world’s most notoriously weather-ravaged regions, “minor” is a relative term.

The paddlers contended with frozen tarps, frosty mornings, sleet and swelling seas on a routine basis. Luckily, knowing how to handle wild weather is what every good expedition is about. “Wat’s nice about 5-metre seas is that it makes everythink else look so small,” Rosen said, adding that he only saw one other kayaking group during his entire trip. “It’s rare in life to get that close to nature for so long.”

As if surviving the elements wasn’t enough to get the pair back in touch with the natural world, the team had many opportunities for an up-close look at some oft the area’s local residents. Sea lions would routinely swim right up and under their kayaks and the pair passed several pods of humpback whales and orcas.

The human residents of isolated coastal villages and fishing communities welcomed them with open arms, offering plenty of local information to help fill the gaps in the 32 marine charts Rosen packed along. Even with food caches strategically placed in major towns on the route, Rosen estimates each 19-foot single person kayak was loaded with about 125 kilograms (275 pounds) of gear.

Even with their weighed-down boats, the kayakers covered an average distance of 43 kilometres (23 nautical miles) per day, thanks, in part, to makeshift sails. On such a lengthy trip, Rosen added, logistical decisions must be made on a regular basis in order to take fluctuating tides, weather and paddlers’ energy levels into account.

Staying up late to ponder navigational charts and listen for updated marine forecasts every evening, Rosen said, added to the adventure and the sense that civilization was always far away. “It’s an amazing feeling to get back to nature, back in tune with the wind and the waves,” he said.

Filed under: Kayaking, News | alaska, Jack Rosen, Travel|No Comments