Category: Alaska

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AP4 (back) and AP8 (front).

Are they sisters? Mother and daughter? Aunt and niece? It’s hard to know. Both are adult females and AP4 has a calf of her own (who is hiding behind her mother in this photo). I have suspicions that AP8 may be the matriarch of AP pod; she does not have any young calves but does usually travel with adult males—AP11 is particularly close to her and is probably her son. Her movements also appear to dictate the movements of the other whales. If she makes a sudden turn, the others usually follow.

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AP18 is the biggest and oldest bull in his pod.

Though he will not sire any calves within his own pod, his sheer size and old age means he (barring any reproductive problems) has likely sired many calves in other pods. For reasons we still don’t totally understand, female killer whales prefer to mate with with old, large bulls. There is likely some aspect of mate choice but recent evidence of infanticide in other killer whale populations suggests that females may not have much say in some instances.

Due to the fact they spend nearly their entire lives underwater, we know virtually nothing about the reproductive behaviors and courtship of killer whales!

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Alaska is vast and fieldwork with marine mammals is often fraught with difficultly. It can be particularly challenging to study the resident killer whales here.

Despite their name, many pods do not stick to one area. Each pod has its own range and some are larger than others. When researching other resident killer whale populations, such as the southern residents, it’s possible to document every individual in the population on a yearly basis. This is not possible in Alaska! Pods go years without being seen and new pods are constantly being discovered.

Take AX27 pod for example. Their section of the southern Alaska resident photo-identification catalog has not been updated in eight years! The main killer whale biologists in Alaska conduct fieldwork in the Kenai Fjords and Prince William Sound. AX27 pod is mainly found around Kodiak, Cook Inlet, and Kachemak Bay and only makes a rare trip to the main study regions. As a result, they have not been officially censused in nearly a decade.

Luckily for me, though, I see them on a regular basis during the summer. In August we found part of AX27 pod and I found that AX84 (I believe) has a calf that has not been documented before! She has one other offspring, AX114, who has sprouted and is becoming a mature bull.

Working in Kachemak Bay, I can help document pods that are not often seen by the biologists at the North Gulf Oceanic Society. Every encounter yields new information about pod structure and behavior. I feel very lucky to be able to work with these animals and learn something new every time I see them!

Killer Whale Personalities

Personalities are not limited to humans. A wide variety of animals display different personalities, which are known as behavioral syndromes in the field of animal behavior. Behavioral syndromes (aka personalities) can be defined as: a collection of traits that characterize an individual’s response and is relatively stable over time. In other words, an individual animal will tend to react a certain way to a particular stimuli pretty much every single time. Behavioral syndromes have been documented in arthropods, mollusks, mammals, birds, reptiles, fish, and amphibians.

For example, animals can differ in their degrees of boldness; when presented with a certain stimuli, some animals are more apt to approach it directly and investigate. Others might be more timid and choose not to approach it. Fascinatingly, personalities can have a big impact on evolution and on an animal’s fitness.

There has not been much formal study into the personalities of killer whales, but if you have spent any time around them, you will notice different behavioral traits in individuals. I have noted this in some individuals in the southern Alaska resident killer whale population. This is AP3, an adult female killer whale from AP pod:

She appears to be a particularly bold individual. Most of the time, the other whales in her pod will ignore our vessel and continue on foraging, traveling, or socializing with one another. AP3, however, tends to approach our vessel nearly every single time we encounter her. Here are a couple of photos of her on the numerous occasions she has surfaced near our boat:

What is particularly interesting is that AP3 has a calf. There is evidence that personalities have a hereditary basis and can be passed on to offspring. Killer whale calves and young females (prior to their first calf) tend to be particularly inquisitive in general so we will have to wait and see if AP3′s calf displays its mother’s bold personality when it matures or after (if female) she has her own calf.

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Sometimes photo-ID is hard, even when you know what pod the whale belongs to.

AP pod’s ID photos were taken 6 years ago. The calves at the time were documented but the saddle patches of young killer whales are often faint and difficult to make out. Those same calves are now juveniles and are much more distinct, but unfortunately matching tbem to their calf ID photos is proving to be a challenge.

Photos from the North Gulf Oceanic Society.

I believe this is AP15 based on the dorsal fin curvature, but I am not 100% sure!

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It’s that time of year again!

There was significant interest for a calendar in my last Instagram poll, so I have created a 2019 Killer Whales of Alaska calendar featuring photos of resident killer whales in Kachemak Bay.

Each calendar is $20 and $5 for shipping! All proceeds will help me with the costs of applying to graduate school. I can ship to anywhere in the US or Canada at this time. Please message me if you would like to purchase one!

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Just half a second before AP3’s calf exploded out of the water next to her!

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Here’s another adult male killer whale that has proven difficult to identify.

I’ve only seen him on one occasion—during the July superpod with AP pod, AS30 pod, and the unidentified pod. He does not belong to AP pod or AS30 pod; you might conclude he must belong to the unidentified pod, but we have to be careful when assigning pod designations. It often takes multiple sightings of a group to be able to determine who is in the pod and who is not (a pod is loosely defined as individuals who spend more than 50% of their time with each other).

When I refer to the “unidentified pod,” I am referring to the assemblage of whales that have been identified as not belonging to any known pod of southern Alaska residents. However, I’ve only actually seen a couple of said whales on repeated occasions, and even then they are not always with the same whales all the time.

It is always my hope that this male and all of the other unidentified whales will show up again, but the reality in Alaska is that groups can go several years without being seen, particularly those that spend time in the western Gulf of Alaska where field studies are not regularly conducted. These whales seem to have avoided detection up until 2017/2018! (However, it’s possible they were sighted by biologists in the past and their photos are sitting in a dusty box or old hard drive somewhere—but so far the people who keep track of these whales haven’t identified them either).

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Killer whales and sea otters—can sea otters tell the difference between friend and foe?

This is a topic I’ve pondered for a while. In Kachemak Bay, Alaska, northern sea otters are incredibly abundant. It’s hard to go more than a few hundred yards without seeing one. As a result, killer whale encounters with sea otters are fairly common. But the reactions of the otters appear to vary greatly—depending on if the whales are transients or residents.

The otter pictured above was snoozing peacefully in this kelp bed while in very close proximity to the AD11s, a resident killer whale pod. Residents, of course, are piscivores and do not consume other marine mammals. The otter appeared to be well aware of the whales and was only startled when our vessel passed by the kelp bed (sorry otter, we didn’t mean to bother you!). I have observed this unusual behavior from other otters on a few different occasions.

While I personally have never witnessed transient-otter interactions in Kachemak Bay, they do occur. Otters are not a primary prey source for transient killer whales but they do sometimes appear to utilize them as “training” tools for juveniles learning to hunt. Other naturalists have told me that when transients appear, the otters panic and make themselves scarce. I have noted that the otters are often difficult to find and far more difficult to approach than usual in the days following reports of transient killer whales.

What’s going on here?

Other studies have documented that Pacific harbor seals are habituated to the calls of resident killer whales but display anti-predator behavior when exposed to the calls of transients. Dall’s porpoises and Pacific white-sided dolphins are known to play with residents and leave when transients show up. These mammals clearly have figured out the harmlessness residents represent and the danger that transients pose. Can otters do the same?

We don’t know. There was a study done in the Aleutian Islands to determine if the otters there have been more exposed to killer whale predation in comparison to otters in British Columbia, where otters are not hunted by transients. The researchers played calls of local transient killer whales to both populations and then compared levels of anti-predator behavior. The Aleutian otters displayed significantly more anti-predator behavior than the BC otters. However, the Aleutian otters also displayed this behavior when exposed to a control sound (a sound that was not of a killer whale). Therefore, it was impossible to conclude if the otters were reacting to novel stimuli or the killer whale calls. Additionally, the researchers didn’t play calls of residents. 

Understanding predator-prey dynamics between killer whales and sea otters is important. A controversial hypothesis posed in 1998 stated that killer whales were responsible for the decline of sea otters in the Aleutian Islands. In 2003, a paper was published blaming killer whales for the decline of megafauna in Western Alaska due to industrial whaling. For killer whale biologists, these papers and hypotheses are incredibly frustrating because they are often presented as fact, when in reality, it is unlikely killer whales ever played a role in sea otter declines. However, there is still much we don’t know, and the more we learn about sea otter interactions with killer whales, the more we can address these hypotheses and perhaps uncover the real cause of sea otter declines. 

The difference one year can make!

The difference one year can make!

AP10 is a young adult male southern Alaska resident killer whale that is still rapidly growing. These two photos were taken almost exactly one year apart: The first photo is from 7/11/17 and the second is from 7/10/18. You can see that his dorsal fin has grown a little taller, a little straighter, and a little wider at the base. Additionally, he has picked up two new nicks in his fin which appeared to be relatively fresh when I took his 2018 photo. We don’t always know where these nicks and tears come from; it’s possible some are from conspecifics, and it’s also possible that they may come from interactions with the environment around them. 

It will be interesting to see how AP10 looks in 2019.