While the winter season here at Southeast Farallon Island
usually focuses on the soap-opera-esque, high stakes drama of elephant seal
pupping and mating season, there are many other marine mammals that utilize the
high productivity and unique location of the Farallon islands in their ocean
travels. These islands are a regular
stopover for other seals and sea lions, as well as their larger ocean
companions – whales and dolphins. Many
whale species are known for their great yearly migrations – humpbacks from
Alaska to Hawaii, grays from the Arctic to Baja - moving from cold but
nutrient-rich northern waters to temperate
(but less full of food) or tropical waters in the winter. These whales make the trips for the same
reason elephant seals return to the Farallones year after year – it’s a great
place to raise a kid. Warmer waters are
better for newborn whales, and they nurse from mom long enough to build up a
nice blubber layer before heading back up to the cold waters of the north.
Most of these whale migrations start in late fall or early
winter, as grays, blues, humpbacks, and more pass by our houses on Southeast
Farallon, one at a time or in large groups with whale blows visible in every
direction. A few months later, the blows
start showing up in the south, as the whales return to summer feeding grounds,
this time often with a new calf in tow.
In the past few years, researchers here on SEFI have noticed a few of
those whale blows in months when they shouldn’t be here. Some “resident” gray
whales – those that don’t migrate all the way south – settle in around the
Farallones, probably taking advantage of the wonderful food supply provided by
our proximity to the continental shelf.
This subset of “residents” may be younger whales that are not yet sexually
mature, and do not need to complete the full migration to the calving and
breeding grounds down south, so they decide the Farallones look like a good
spot to stay for the winter.
We keep track of these resident whales, as well as the
migrating ones and any dolphins who happen to pass our way, with our daily
“Cetacean Watch.” Twice a day, and
sometimes more often if the weather and visibility cooperate, we climb the
trail to the lighthouse, where visibility on a clear day is 40+ miles in all
directions, and set up with our scope, binoculars, and an iPad. The iPad is a new addition to our daily whale
watches, not just because it’s easier to use its built-in GPS and compass when
spotting whales, but because of a new app called “Spotter Pro,” by Conserve.IO.
This app (currently only for Apple’s iPad & iPhone) allows users to collect
field data of animals, plants, and other environmental information, and
provides a unique opportunity to participate in “citizen science.” Recently, the app has been used to track and
upload sightings of whales and dolphins off the California coast. We use Spotter Pro to upload real-time
information on the locations of these animals around the Farallones. By providing information on where they are,
the app helps to reduce the chances of whales being struck by large vessels
when they’re in California
shipping lanes.
A gray whale passes close by SEFI |
Ship strikes are one of the biggest threats to whales and
dolphins, and often go unnoticed – dead animals often either sink out at sea or
wash ashore too decomposed to determine the real cause of death. Reducing the co-occurrence of whales and
large boats (making sure they’re not in the same place at the same time) is the
best way to prevent ship strikes, and using the Spotter Pro app to map the
locations of whales and dolphins could be a simple, user-friendly and openly
available way to prevent co-occurrence.
Recent changes in the size and locations of California’s shipping lanes
were implemented with whale protection in mind, and with both researchers (like
us on SEFI) and citizens out on boats or onshore uploading information on where
they see whales, we can assess the effectiveness of these changes while
preventing strikes from occurring.
A screencap of Whale Alert (from iTunes app store) |
From a recent SEFI cetacean survey |
These shipping lanes pass close by SEFI, and while drinking a morning cup of coffee on the porch, it’s not unusual to see huge container
ships cruising by on the horizon, along with 5 or 6 blows closer to shore, while
looking in just one direction. One of
the main goals of Spotter Pro and its East coast sister app, Whale
Alert, is to allow
ship captains access to real-time location information, so they can either
avoid areas with lots of whales or slow down while passing through them. Our unique location in the midst of these
shipping lanes and our ability to look for whales on a daily basis provides
important information on their location – especially for the resident whales
that decide to stick around. The
Farallones might be a great whale buffet, but they’re also in the middle of some
heavy ship traffic, and providing daily information on whales in the area will
help reduce their chances of being run over.
It has been a banner year for whale
watching off the California coast, and this season it seems they are sticking
around longer than usual, a strange occurrence that only emphasizes the need to
protect them from collisions. Here at
SEFI, we are seeing blue whales almost every day, unusual for this time of
year, and we’ve had a few humpbacks also making a later trip down south, in
additional to a few pods of Risso’s dolphins.
Last week, we caught a glimpse of a distinctly v-shaped blow among some
southbound gray whales, which usually have bushy or heart-shaped blows. Right whales, one of the most endangered
species of marine mammals, have very prominent v-shaped blows, though some gray
whales have also been seen with a larger divot in their blow, making it appear
v-shaped. Sightings of North
Pacific right whales are extremely rare, and it is even more rare to see
one this far south. Two sightings
occurred earlier this year off the coast of British Columbia, the first for
that area in 62
years. Unfortunately, we couldn’t
confirm the identity of the whale with the v-shaped blow, but we alerted NOAA
and other organizations further down the coast, hoping that the southbound
whale would be seen and confirmed somewhere on its travels.
The v-shaped blow of a
right whale (left) is notably more separated than the bushy, heart-shaped blow
of a gray whale (right)
|
Our great gray whale migration is just starting to pick up,
and I look forward to seeing more and more of their huge spouts passing us by
every day (along with any other random whale and dolphins that may appear), while trying our best to conserve and protect them along with all
the other wonderful creatures at SEFI – residents and visitors alike.
1 comment:
There have been no records of a right whale along the west coast south of British Columbia since 1998 when there were 1-2 sightings off Pt Sur and in Monterey Bay. A complete list of the sightings off the west coast since 1925 can be found at: http://www.sfcelticmusic.com/js/RTWHALES/WestCoast_sightings.htm
For a thorough review of the status of the right whale in the North Pacific I recommend the article in Wikipedia.
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