Monthly Archives: January 2016

Porpoises

Kodiak Wildlife, Porpoise, , ,

 

Two species of porpoises frequent the waters near Kodiak Island: The harbor porpoise and Dall’s porpoise. Our guests often ask if the terms dolphin and porpoise can be used interchangeably, and the answer is no! Porpoises and dolphins are as distinct as cats and dogs, and they belong to different taxonomic families. Porpoises are smaller than dolphins, and they are stockier and lack the characteristic “beak” of a dolphin. Porpoises have spade-shaped teeth while dolphins have conical teeth. Porpoises grow faster and reach sexual maturity at a younger age than most dolphin species. Most porpoise species are less social than dolphins, and porpoises usually hang out alone or in small, fluid groups.

Harbor, Porpoise

The harbor porpoise is one of the smallest oceanic cetaceans, and it is the smallest cetacean found in Alaska. The body of a harbor porpoise is stocky and rotund through the mid-section, tapering to a slender tail stock. An average harbor porpoise is five ft. (1.5 m) in length and weighs 130 lbs. (60 kg). The body is dark gray or dark brown on the back, fading to a lighter gray on the sides. The throat and belly are white, but there may be a streak of gray on the throat and a dark chin patch. The flippers are dark in color, and a dark stripe extends from the flipper to the eye

Harbor porpoises primarily eat fish, but they may also feed on squid, octopus, and crustaceans. In Alaska, they feed on fish such as cod, herring, and pollock, and it has been estimated that they eat approximately 10% of their body weight each day. They surface in a slow roll and rarely “porpoise” out of the water. They are shy and seldom approach vessels, and they never play in the bow wake like Dall’s porpoises do. Large sharks, dolphins, and killer whales all prey on harbor porpoises.

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Dall’s porpoise is easily identified by its striking black and white coloration that resembles the markings of a killer whale and the characteristic rooster-tail splash it often makes when surfacing. A Dall’s porpoise averages six ft. (1.8 m) in length and weighs approximately 270 lbs. (123 kg). It has a stocky, muscular body and is particularly robust through the mid-section. It has a small, round head that slopes steeply to a short, poorly defined beak. It has small teeth shaped like grains of rice. The teeth are the smallest of any cetacean species, and they often do not rise above the surface of the gums. The color pattern of Dall’s porpoises varies between individuals, but most are black on the upper sections of the body, with large oval-shaped white sides and white bellies. A band of white usually borders the flukes and the dorsal fin.

Dall’s porpoises forage at night, and they feed on small fishes and cephalopods. In Alaska, they eat squid and small schooling fishes such as capelin, lantern fish, and herring. A Dall’s porpoise consumes approximately 28 to 30 lbs. (12.7-13.6 kg) of food each day.

Dall’s porpoises are the fastest of the small cetaceans, reaching speeds of 35 mph ( 56.3 km/hr), which is a tie with killer whales for the fastest marine mammals. You can often see them from a distance, slicing through the water and creating a V-shaped splash called a rooster-tail splash. This splash creates a hollow cone that allows the porpoise to breathe under the surface of the water. Dall’s porpoises rarely engage in acrobatic behavior such as breaching or leaping out of the water, but they will charge a rapidly moving boat to ride the bow or stern waves, and they may remain in the bow wave for half an hour or more, darting in and out of the wake and making steep-angled turns.

Killer whales and sharks may prey on Dall’s porpoises, but because of their speed, agility, and fairly large body size, they often can escape predators. About 30 Dall’s porpoises per year die as a result of being caught in fishing nets in Alaska. It is unclear why they get caught in salmon nets, since they don’t feed on salmon, but many of the deep-sea species they do feed on come to the surface at night when these porpoises feed, making it more likely they will run into nets.

 

 

 

 

 

Winter

Living in the wilderness on Kodiak Island, , , , , ,

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I did not take the above photo this winter, I took it four years ago, the last time we had a cold winter on Kodiak Island. If I posted a photo from this winter, it would show torrential rain and heavy wind. I’m not complaining about a warm winter, because there is nothing fun about hauling water after the pipes freeze, and life takes a nosedive when the sewer freezes. The worst part about a cold winter here, though, is not the inconveniences of everyday life, but it’s watching the wildlife suffer as they struggle to find food and keep warm. Four years ago, we had deer die in our yard or die curled up under one of our buildings from cold and hunger several times a week. I knew when a deer was about to die because he’d look at me with glassy eyes and not even bother to move out of my way when I walked down the path past where he was standing. Sitka black-tailed deer were introduced to Kodiak Island, and the winter climate here is often on the edge of what they can tolerate to survive.

The deer have had good winters the last few years, and this may prove to be the warmest yet. When it is very cold, we have several deer in our yard, searching for grass that may still have some nutrients. This winter, we’ve seen few deer in our yard, because it is warm and there is no snow on the ground. It was 46⁰ the other day in mid-January, but the weather has not been pleasant this winter. We’ve been pounded by one low-pressure system after the next, bombarded by high winds and heavy rain. One storm out of the north in December slammed waves into our dock and sent a 55-gallon drum full of gas and two 100-lb. Propane tanks into the water. Mike has had to repair the dock twice from storms, but luckily, many of our storms have been from the south, and the cove where we live is protected from a southerly swell.

The ceaseless wind and rain make doing anything outdoors unpleasant, and the heavy clouds accentuate the already dark days. I love the peace and quiet here in the winter, but I am beginning to dream about going someplace sunny and calm and maybe even going out to dinner and a movie (I know, now I’m getting carried away). Luckily for me and my psyche, we are leaving on vacation next week!

While we are away, our friends, Ryan and Ruby, will be staying here, battling storms and catering to the whims of our very spoiled cats. Ryan and Ruby are the best caretakers we could ask for, and we don’t worry about our home while they are here. Our cats love them (possibly more than they love us!), so I know the furry little beasts will be even more spoiled when we return.

Once we leave here, we are flying straight to Las Vegas for extreme culture shock and a hunting and outdoor show, where we have a booth. That’s a week of hard work and stress because we go from talking to no one to talking to strangers all day. Vegas is also a great deal of fun, though, because we will see several friends and spend many hours laughing. After Vegas, we are flying to New Zealand for a two-week hiking, biking, kayaking tour of the South Island, and I am excited about that. I’ve never been to New Zealand, but I’ve only heard good things about the breathtaking scenery and the friendly people. After we return from New Zealand, we will spend some time in Anchorage and Kodiak, buying supplies and running errands. We’ll be home by mid-March.

I have a few posts planned for while I’m away, and my good friend, Marcia Messier, has agreed to write some guest posts for me. I’ll try to send a post from New Zealand to let you know about that adventure, but I may miss a post or two, so I’ll apologize in advance.

My next Mystery Newsletter will be about the biggest mass murder in Alaska history. Be sure to sign up on my home page if you want to receive my monthly newsletter.

 

 

 

More About Toxic Algae

Algae, , , , ,

Last week I discussed the toxic algae that cause paralytic shellfish poisoning, and this week, my post is about other species of toxic algae, the symptoms they cause and their impacts on humans and animals.

Amnesic Shellfish Poisoning (ASP) is caused by domoic acid, a biotoxin that is produced by the diatom Pseudo-nitzschia. Fish and shellfish, including bivalves and crab, can accumulate domoic acid with no ill effects, but when humans, other mammals, and birds consume the toxic fish and shellfish, they suffer the effects of ASP. As with paralytic shellfish poisoning (PSP), cooking or freezing the toxic organisms does not lessen the toxicity. This past summer, scientists estimated that the largest-ever bloom of Pseudo-Nitzchia occurred, stretching from California to Southeast Alaska and prompting Oregon and Washington to issue emergency closures for their commercial shellfish fisheries. The bloom was not obvious from sea level, but satellite images showed that a large swath of the ocean had been overtaken by the single-celled algae.

Domoic acid can be fatal if consumed in high doses. It is a neurotoxin that inhibits neurochemical process and can cause short-term memory loss and brain damage. Symptoms appear within 24 hours of ingesting the toxic organism, and they include vomiting, nausea, diarrhea, and abdominal cramps. In more severe cases, neurological symptoms such as a headache, dizziness, confusion, disorientation, vision disturbances, loss of short-term memory, motor weakness, seizures, profuse respiratory secretions, hiccups, unstable blood pressure, cardiac arrhythmia, and coma may occur within 48 hours or up to three days.

In 1987, ASP caused the deaths of three people on Prince Edward Island who ate infected mussels. There is no antidote for domoic acid. Of the 107 confirmed cases, there were four deaths and a few cases of permanent short-term memory loss. Since March 2007, the large increase in marine mammal and seabird strandings and deaths off Southern California has been linked to the recent blooms of toxic algae, and most of the dead animals tested positive for domoic acid.

Ciguatera is not something we worry about in Alaska. It is a foodborne illness caused by eating certain tropical and subtropical reef fish. Ciguatoxin has been found in over 400 species of reef fish, and it can also occur in farm-raised salmon. It is caused by several species of dinoflagellates such as Gambierdiscus toxicus that adhere to coral, algae, and seaweed. The toxic dinoflagellates are eaten by herbivorous fish that are in turn eaten by carnivorous fish that may then be eaten by larger carnivorous fish. The toxin is biomagnified as it moves up the food chain, so predators near the top of the food chain are likely to be the most toxic. Like the other toxins we have discussed, ciguatoxin is odorless, tasteless, and cannot be broken down or removed by cooking.

Symptoms of ciguatera in humans include nausea, vomiting, and diarrhea, usually followed by headaches, muscle aches, ataxia, numbness, vertigo, and hallucinations. These neurological symptoms can persist and are sometimes misdiagnosed as multiple sclerosis. Interestingly, some ciguatera toxins can be passed from an infected individual to a healthy individual through sexual intercourse, and diarrhea and facial rashes can occur through breast feeding in an infant whose mother has been poisoned. The symptoms of ciguatera can last from weeks to years, sometimes as long as 20 years. Most people do recover over time, but symptoms often reappear.

Cyanotoxins are produced by bacteria called cyanobacteria (blue-green algae). Cyanobacteria is found in both fresh and salt water, and blooms often form thick mats or scum over the surface of the water. Sometimes the blooms are such a bright green that they look like paint floating on the water. Cyanotoxins include neurotoxins, hepatotoxins, cytotoxins, and endotoxins. The cyanobacteria neurotoxin BMAA can cause neurodegenerative diseases such as ALS, Parkinson’s disease, and Alzheimer’s disease. Cyanotoxins are toxic to animals as well as humans.

I am intrigued by toxic algae, and I am concerned that as our oceans warm and receive more nutrients from man-made runoff, toxic algae blooms will plague not only humans but also fish, birds, and marine mammals. The dinoflagellates, diatoms, and bacteria that produce marine toxins are tiny organisms that we can’t even see, but their impacts are huge.

I promise a less-technical post next week, and please don’t hesitate to leave a comment telling me what you’d like me to write about. Also, if you are interested in true crime, don’t forget to sign up for my Mystery Newsletter. As soon as you sign up, I’ll send you my first newsletter.

Toxic Algae

Algae, , , , ,

 Blooms of toxic algae are nothing new. Toxic algae occur naturally in both fresh and salt water, and algal poisonings have happened many times over the centuries. What is different is the frequency and magnitude of toxic blooms in some areas of the world. Environmental conditions such as changes in salinity, increasing water temperature, and an influx of nutrients can trigger an algal bloom, and once the bloom begins, it can increase exponentially in a short period. As our oceans get warmer, it is likely we will see even more of these toxic blooms in upcoming years. This past summer, a massive bloom of the algae Pseudo-nitzschia that produces domoic acid, a powerful neurotoxin, shut down the Washington state commercial fishing season for Dungeness crab, causing millions of dollars in lost revenue, and this toxic bloom possibly caused the deaths of at least 44 whales in Alaska.

In my next two posts, I will dive into the topic of toxic algae in more detail. There are several species of toxic algae, and I will discuss four types of algal poisonings caused by toxic blooms: Paralytic shellfish poisoning, amnesic shellfish poisoning, poisoning caused by ciguatera toxin, and cyanotoxic poisoning.

     Paralytic shellfish poisoning (PSP) is caused by a microscopic single-celled dinoflagellate algae in the genus Alexandrium. Bivalve shellfish, such as mussels and clams, may feed on these dinoflagellates and concentrate PSP toxins that are not harmful to the bivalves but are poisonous to humans, other mammals, and some birds that feed on these bivalves. Crab can also concentrate the toxin in their viscera.

In my novel, Murder Over Kodiak, Dr. Jane Marcus is working to develop a small, inexpensive kit that would allow a person to dig a bucket of clams and easily test them to make sure they aren’t toxic before eating them. She explains the difficulty of her research to FBI Agent Nick Morgan by telling him that PSP toxins are called saxitoxins, which are produced by dinoflagellate algae. These dinoflagellates do not produce just one toxin, but 21 molecular forms of saxitoxin, and these 21 forms can undergo transformations that can change one toxin into another. The forms vary in toxicity. A person’s stomach acid can change the original saxitoxin into another form that is six times more toxic. Furthermore, some species of bivalves can hold higher levels of the toxin than other species can, and some species, such as butter clams, have the ability to bind the most highly toxic forms of saxitoxin. Steamer clams, on the other hand, transform saxitoxin into one of its less toxic forms.

In my novel, a lady eats toxic clams for dinner and suffers the textbook symptoms of severe PSP. Twenty minutes after eating the infected bivalves, her lips begin to feel numb, and her fingers and toes start to tingle. Soon, she is dizzy and sick to her stomach, her breath coming in short gasps. Forty-five minutes later, she can’t walk or talk and is barely breathing. She stops breathing in the Coast Guard helicopter on the way to the hospital.

Saxitoxins are neurotoxins that block the movement of sodium through nerve-cell membranes, which stops the flow of nerve impulses, causing numbness, paralysis, and disorientation. The toxicity of saxitoxins is approximately 1000 times greater than cyanide, and the symptoms begin to appear soon after consuming the toxic shellfish. There is no antidote for PSP, and there is nothing that can be done to toxic shellfish to render them safe for consumption. Saxitoxins do not dissolve in water, and they are heat and acid-stable. In other words, cooking the bivalves will not break down the toxins. Some shellfish store the toxin for weeks, and others, such as butter clams, can store the toxin for as long as two years. All cases of PSP require immediate medical attention, and some may require life support equipment to save a victim’s life. If the dosage of PSP is low and if proper medical treatment is administered, the symptoms usually diminish in nine hours.

The worst historical account of PSP poisoning occurred in Southeast Alaska in July 1799 when more than 100 Russians and Aleuts died from eating clams and mussels gathered from Peril Straits near Sitka. The most recent cases occurred last summer when two people died in Southeast Alaska, one from eating a cockle and the other from eating a Dungeness crab, and three people became ill in Kodiak from eating butter clams. Cockles tested in Southeast Alaska last summer had a level of PSP that was 2,044 parts per million. Anything over 80 parts per million is considered unsafe for human consumption. PSP also kills sea otters, and it probably is toxic to other mammals. It is known to affect shags, common terns, common murres, Pacific loons, sooty shearwaters, and possibly many other bird species.

As a side note, I am not the first person to use algal toxins as part of the plot of a story, and I am in good company. In 1961, hundreds of crazed birds, mostly sooty shearwaters, attacked the town of Capitola, California, crashing into street lamps and through glass windows and attacking people. These birds normally live offshore, but it is assumed that they dined on small fish that had eaten toxic Pseudo-nitzchia algae, and the birds became disoriented after succumbing to amnesic shellfish poisoning. Alfred Hitchcock based his screenplay The Birds on this incident. I’ll discuss amnesic shellfish poisoning in more detail next week.

Once again, don’t forget to sign up for my monthly Mystery Newsletter if you haven’t already done so. I will send you my first story as soon as you sign up. A few people have had trouble signing up on the form on my website. If the form doesn’t work for you, leave me a message, and I will be happy to add you to my list. Also, if you would like to have my weekly blog post delivered to your e-mail inbox, leave a comment, and you will be automatically signed up for that.

Arctic Tern (Sterna paradisaea)

Birds, Kodiak Wildlife, , , , ,

The Arctic tern (Sterna paradisaea) is one of three species of terns found in Alaska. The other two species are the Aleutian tern (Onychoprion aleutica) and the Caspian tern (Sterna caspia). Terns belong to the family Laridae, which also includes gulls.

Arctic terns have a circumpolar range. They breed in the Arctic and subarctic regions of North America, Europe, and Asia, and they winter at the southern tips of Africa and South America, all the way to the edge of the Antarctic ice. In the United States, Arctic terns nest as far south as New England on the east coast and Washington State on the west coast. In Alaska, the Arctic tern has the largest breeding range of any Alaskan water bird. Arctic terns nest from Point Barrow through the Southeast Panhandle, and everywhere in between those two points.

Since Arctic terns breed in Arctic and subarctic areas and then migrate as far as the edge of the Antarctic ice to spend the winter, biologists believe they have the longest migration of any animal. The only animal whose migration may rival that of the Arctic tern is the sooty shearwater which migrates between New Zealand and the North Pacific. In a 2010 study, biologist Carsten Egevang and his colleagues fitted 11 Arctic terns with miniature geolocators, and they learned Arctic terns migrate even further than was previously believed. Some individual terns in the study traveled nearly 50,000 miles (more than 80,000 km) round trip. Because Arctic terns spend summer in the high latitudes of the northern hemisphere and then travel to the high latitudes of the southern hemisphere for the summer there, they see more sunlight every year than any other animal species on the planet.

Arctic terns measure 14 to 17 inches (36-43 cm) in length and have a wingspan of 29 to 33 inches (74-84 cm). Their bodies are white or gray during the breeding season, and a black patch covers the head and forehead. They have a sharply pointed red bill and short red legs. Their deeply forked tail resembles the tail of a swallow and is the reason for their nickname, “Sea swallow.” Terns are agile and quick in the air and can even hover above the water while searching for food. Because they have small, webbed feet, terns do not swim well and do not remain in the water any longer than it takes to catch their prey. A tern flies with its bill pointed down toward the water, and when it sees a fish or other prey, it dives into the water, grasps the prey, and flies away with the fish in its beak. During the non-breeding season, a tern’s legs and beak turn black, and the black patch on the head shrinks. Also during the non-breeding season, terns molt and lose most of their feathers. If they lose their feathers faster than they can be replaced, they may be flightless for a short period.

Arctic terns mate for life, and in Alaska, they arrive at their breeding areas in early to late May. During their courtship, the male performs a “fish flight.” He carries a fish in his bill and flies low over the female on the ground. If she sees him, she will join him in a high climb and flight. Terns nest in solitary pairs or colonies of a few to several hundred pairs. A tern’s nest is little more than a shallow depression in the ground, and nests usually have little or no lining material. Terns nest near fresh or salt water on beaches, spits, and small islands. The female lays one to three eggs that are brown or green and lightly speckled. Both sexes incubate the eggs, and the eggs hatch in about 23 days. The young terns immediately leave the nest and hide in nearby vegetation. The parents catch small fish to feed the chicks for the next 25 days until the chicks have fledged. Arctic terns are very aggressive during the breeding season, and they will attack intruders by crying loudly and repeatedly diving at the intruder’s head. Less than three months after they arrive at their breeding colonies, Arctic terns begin their long migration south.

Arctic terns eat small fish, insects, and invertebrates. During the non-breeding season, they are pelagic and forage at the edges of the pack ice, icebergs, and ice floes near shore.

The worldwide population of Arctic terns is between one and two million breeding pairs. Several hundred thousand pairs nest in Alaska. Because terns nest on the ground, their eggs, and chicks are susceptible to predation by foxes, rats, raccoons, gulls, and other seabirds. Arctic terns are also susceptible to pollution, human disturbance, and decreased food availability due to warming ocean temperatures. Arctic terns may live into their late twenties or early thirties.

I will be sending out my next Mystery Newsletter soon, so if you haven’t signed up for my free newsletter, you can do that here.

 

 

 

 

 

 

Dead Whales

Fin Whale, Humpback Whale, Kodiak Wildlife, Living in the wilderness on Kodiak Island, , , , , , , , ,

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This summer and fall several dead whales were spotted in the Western Gulf of Alaska, with the majority clustered around Kodiak Island. The number of deaths now stands at 43 whales, including fin whales, humpbacks, and, at least, one gray whale. So far, none of the whale carcasses that could be accessed have been in good enough shape to provide a clue to the cause of the deaths, but the National Oceanic and Atmospheric Administration (NOAA) is so concerned that they have classified the deaths an “unusual mortality event” (UME). A UME is defined as a significant die-off of a marine mammal population that demands an immediate response.  This designation triggers a focused, expert investigation into the cause.

At nearly the same time dead whales were being discovered in Alaska, whales were also dying off the coast of southern Chile. In November, biologists in Chile announced that in June, 337 sei whales were found beached in a region of southern Patagonia in Chile. This is one of the largest whale strandings ever recorded. While these whales were found beached, researchers think they died at sea and washed up on the beach.

What caused the deaths of the whales in Alaska and Chile, and did they all die from the same cause? Sadly, we may never know the answers to these questions, but biologists in both Alaska and Chile suspect a harmful algae bloom may be the culprit. Most of the dead whales are baleen whales that feed low on the food chain, making them highly susceptible to a toxic algae bloom. What makes this scenario even more believable is that abnormally warm water conditions in the Pacific Ocean this summer led to a massive toxic algae bloom of the single-celled algae Pseudo-nitzschia.

Pseudo-nitzschia produces domoic acid, a powerful neurotoxin. Under normal circumstances, a domoic acid concentration of 1,000 nanograms per liter is considered high, but in mid-May, concentrations 10 to 30 times this level were found in the North Pacific. Domoic acid accumulates in zooplankton, shellfish and fish, and when mammals and birds eat these organisms, the accumulated acid over-stimulates the predator’s nervous system, causing the animal to become disoriented and lethargic. Ingestion of high concentrations of domoic acid can lead to seizures and death.

In addition to Pseudo-nitzschia, the warm ocean water conditions in the Pacific also may have resulted in blooms of other toxic algae, but if toxic algae are the culprit, why aren’t other mammals or birds dying as a result? These are questions researchers are scrambling to answer, and recently they have been rechecking photos to see if there is evidence that the whales may have starved to death. Warmer ocean conditions could have led to a reduction in the prey of these huge whales that must eat  continuously all summer to build a blubber layer that will last them through the winter.

There is no time frame for when a UME must end, and biologists plan to keep researching the whale deaths for a while longer, but they admit the cause may never be known. One dead whale washed up a few miles from where we live, but we saw many other whales this summer that seemed to be feeding and acting normally, and I hope the whale deaths were an anomaly that won’t continue next spring and summer.

Next week I’ll go into more detail about toxic algae blooms. For those of you who have read my novel, Murder Over Kodiak, you may remember that Jane Marcus was studying paralytic shellfish poisoning, a condition caused by a poisonous algae bloom, and since toxic algae have been in the news this year, I think it will be an interesting topic to tackle.

I am FINALLY ready to send my first Mystery Newsletter to those who have signed up for my list. I plan to mail it on January 6th, so if you haven’t signed up for my list yet, do so soon on my home page. My first newsletter will chronicle the events of the McCarthy massacre of 1983. Thanks, and be sure to leave a comment to let me know what you think of my post!