Did you know a mature male northern fur seal can weigh over 600 pounds? That’s a lot larger than Flaherty and Leu, the two fur seals who joined the Seattle Aquarium last March. They’re still young and growing, though: Flaherty is three years old and currently weighs in at approximately 90 pounds; Leu is four years old and tips the scales at around 120 pounds. When fully grown, they’ll weigh between 350 and 600 pounds, depending on the season. Mature female fur seals, on the other hand, are much smaller. An adult male fur seal can be up to six times larger than an adult female! Sexual dimorphism is the term for size difference between males and females—and the sexual dimorphism between male and female fur seals is the largest of any marine mammal species.
Northern fur seals are also distinguished by their big eyes, which help them see at night; the large flippers that propel them through open water; and, maybe most notably, their thick, luxuriant fur. That fur made them especially attractive to hunters for many years. As a result, northern fur seals are listed as “depleted” under the Marine Mammal Protection Act. Their total population, estimated at 1.1 million, is far less than it used to be—and their numbers are declining.
What’s the reason behind the population decline? That’s a question that’s been on many researchers’ minds, and the answers have been slow in coming. Field research on northern fur seals is no easy task since the animals breed in the summer on remote islands in the North Pacific and, until recently, no one truly understood where they went the rest of the year. As it happens, more than 50 percent of the wild northern fur seal population breeds on the Pribilof Islands in Alaska—so it’s there that researchers from the National Oceanic & Atmospheric Administration’s (NOAA’s) National Marine Fisheries Service (NMFS) focused their efforts. Researchers attached satellite-linked time depth recorders (SLTDRs) to the animals; the SLTDRs then transmitted data on location, time, and depth of dives in real time so that animals could be followed while at sea. The collected data confirmed that northern fur seals are amazing distance swimmers and travel thousands of miles in search of food. Much more remains to be learned about northern fur seals, especially with regard to their population decline.
Fur seals in zoos and aquariums are a rarity as well: just seven are on exhibit in the United States, including our own Flaherty and Leu. The Seattle Aquarium has a long history with northern fur seals. We’re one of just three facilities in the United States—and the only one on the West Coast—to exhibit them. In 1983, our facility became the first in the world to have a northern fur seal conceived and born in human care. A total of five fur seals born here lived to adulthood. Isaac, the final of these, was born in 2000 and moved to the New England Aquarium in 2009 as part of a collaborative breeding loan. While there, he sired our own Flaherty—which made us especially happy to welcome him to the Aquarium last year. It’s a fur seal full circle!
Interested in learning more about northern fur seals? Read our fur seal fact sheet, then come to the Aquarium to meet Flaherty and Leu—and check out the interactive kiosk next to our fur seal exhibit!
The Seattle Aquarium is making some changes to our annual giant Pacific octopus (GPO) census, which means we won’t be doing the annual count (which in recent years has been conducted over the Martin Luther King, Jr. holiday weekend) this winter.
Going forward, we’ll conduct the surveys in October rather than January, due to the weather-related complications we’ve regularly experienced in the past couple of years. More importantly, in an effort to be more consistent with our census, we’ll focus the annual octopus counts on six dive sites. Our hope is that the consistency will provide some scientific insight to GPO populations over time.
Why focus on six sites? Over the last 16 years, divers have surveyed many dive sites throughout Puget Sound and, while this has given us a general overview of where octopuses are in the Sound, it hasn’t been able to tell us much about the octopus population as a whole.
That’s one problem with the data we’ve collected. The other is that we haven’t had a single dive site surveyed every year—which prevents us from getting a complete picture of what is going on year to year. Taking advantage of the opportunity presented by the recent creation of octopus protected areas in Puget Sound, we reworked our previous approach to create something that will hopefully provide us with interesting and useful data, and a more complete picture of what’s going on with our GPO population.
The new census will look very similar to what we’ve done in the past, but we’ll now be focusing our efforts on comparing six dive sites. Three of the sites are in the new octopus protected areas, and three are in unprotected areas. And, as noted previously, we’ve moved the timeframe so that the census will now take place in October. Our hope is that October will offer a better window of weather, allowing more opportunities for people to get out and dive.
One thing that hasn’t changed: we’ll continue to use the local dive community to help us gather this data—including charter boat dives, which proved to be a big success and lots of fun in 2015. We’ll provide more information about the dive sites and specific dates later this year. Stay tuned!
You might already know about the birds and the bees as they relate to birds and bees…but what about the birds and the bees for the fishes of the sea? Between winter and spring is the time when most of the Aquarium’s cold-water fish reproduce, and keen-eyed visitors may be able to see signs of it in our exhibits—if they visit soon!
Keep reading to learn about three types of reproduction and what to look for on an upcoming visit to the Aquarium! FYI, reproduction for our warm-water fish doesn’t follow this same seasonal cycle; it may take place year-round and be time to lunar cycles instead of seasons.
How does it work? The mother lays eggs, then the young hatch out of those eggs. Ninety percent of bony fish and 43 percent of cartilaginous fish reproduce this way.
What to look for: A spotted ratfish cruising around the Underwater Dome with two egg cases trailing behind it. Also recently sighted in the same exhibit: whitish clusters of lingcod eggs. On a nearby rock, you may be able to see a male lingcod guarding more of these eggs.
How does it work? The young develop inside the mother, then she gives live birth (similar to human reproduction). Surf perches are some of the only true viviparous fish. Certain sharks, such as hammerheads, blue sharks and bull sharks, also reproduce this way.
What to look for: If you see blue striped perch in the Underwater Dome that are just a couple inches long, you are seeing fish that were born in the exhibit! Most of the fish that are born or hatched at the Aquarium are small enough to return to Puget Sound via the open-water system that supports the exhibits in which we feature fish native to our local waters. But these young perch are anywhere from 1.6 to 2.4 inches long at birth, too large for the open-water system, and as such are one of the few larval fish that may remain at the Aquarium for the duration of their lives.
How does it work? The eggs hatch within the mother’s body, and then she gives live birth to the young. From the outside, this looks just like viviparous reproduction. The big difference is that there is no placental connection between the mother and young—instead, the young are nourished by an egg. Rockfish are ovoviviparous—as well as rays and some sharks.
What to look for: The baby bump on a yelloweye rockfish in our Window on Washington Waters exhibit. At her mature size, she may release 500,000 live little rockfish. The young will be about one-fifth of an inch long when they’re born, which usually happens around the height of the spring plankton bloom (so those young fish have food) and at night (for protection).
What a year it was! There’s a lot to look forward to in the new year, but first a look back. We’ve rounded up our top 15 animal highlights from 2015, take a look!
1–2: Welcome to Leu and Flaherty
Fur seals Leu and Flaherty joined us last March from New England Aquarium. At 4 and 3 years old, respectively, they are relative youngsters and it will be a treat to see them grow up. Leu now weighs in at 102 pounds; younger Flaherty is tipping the scales at 78 pounds. They’ll be between 350 and 600 pounds when they’re fully grown!
3: Sweet young puffling
What’s a puffling? A puffin chick, and we were delighted to welcome one on August 1, 2015. We later determined that the chick is a girl.
4–12: Orcas galore
It was a banner year for the Southern Resident orca community—eight baby orcas were born in 2015, making it the biggest baby year since 1977, when nine calves were born to J, K and L pods (the group that comprises the Southern Resident community). Best wishes to all the new babies and their moms in the coming year!
13: Hello, Hogan
After much anticipation, harbor seal Hogan arrived at the Seattle Aquarium from Point Defiance Zoo and Aquarium (PDZA) on December 8, 2015. Hogan is the 2 ½- year-old offspring of our own Q and PDZA female Shila. Come meet him on your next visit to the Aquarium!
14: Mishka, Mishka, Mishka
Northern sea otter Mishka arrived in late January, 2015—and was diagnosed with asthma late last summer. She’s since learned how to use an inhaler to receive the medicine she needs; read our previous blog post for the story.
15: Salmon surge
2015 included the largest run of fall chinook salmon that the Columbia River has seen since 1938. At the Seattle Aquarium, we celebrated the hatching of our chinook salmon in December—read our blog post for details!
A project that finished on time and on budget? Now that’s something to celebrate!
To recognize the timely repayment of a loan from the City, the Seattle Aquarium Society recently presented a check for $1.45 million to Mayor Ed Murray. This was the final payment for the bridge financing of $5.2 million for the 2005–2007 New Currents Aquarium expansion project. The arrangement was part of a $42 million public/private partnership that restored the structural integrity of historic Pier 59 and expanded the Aquarium exhibit and public spaces by 30 percent.
Congratulations and thanks to the Aquarium Society campaign, chaired by Ted Ackerley and Stuart Rolfe, which raised $20 million of the project costs. With the addition of a new entrance on Alaskan Way, major new exhibits and a café, as well as expansion of the gift shop and evening event facilities, the successful project helped increase Seattle Aquarium attendance to 800,000 visitors per year and secure its place in the top 10 aquariums in the nation by attendance.
Pictured left to right: Seattle Aquarium President & CEO Robert W. Davidson, Deputy Parks Superintendent Christopher Williams, past Aquarium Board Chair and Campaign Co-Chair Ted Ackerley, Aquarium Director of Finance & Administration Ryan Dean, Seattle Mayor Ed Murray and Parks Superintendent Jesus Aguirre.