Robin Barefield's Blog, page 7

What Can a Skeleton Tell You?

Last week, I asked you if you discovered a skeleton or a pile of bones in the woods, would you be able to read the skeleton and understand its secrets? In my last post, I discussed how a forensic anthropologist determines gender from skeletal remains. This week, I’ll explain how a forensic anthropologist deduces the height and race of an individual by looking at his skeleton.

Race:

Anthropologists shrink away from the term “race” and instead
refer to an individual’s ancestry. Humans are often a mixture of ancestries, so
race can be difficult to determine from
skeletal remains.

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Skulls in people from European ancestry are generally long
and narrow. The eye sockets appear rounded with squared margins. The narrow
nasal aperture sits high on the face, and the nasal bridge is prominent and
sharply angled. The teeth appear small and are spaced closely together.

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Asian skulls have circular eye sockets and heart-shaped
nasal apertures. The nasal bridge is less pronounced than it is in European
skulls, and it is gently angled. Asian skulls have shovel-shaped upper
incisors.

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African skulls have rectangular eye orbits. The nasal
aperture is wide, and the nasal bridge is flat. The jaw protrudes from the rest
of the face, and the teeth are large and spaced wider apart than those in
individuals with European or Asian ancestry.

Height or Stature:

A close correlation exists between the length of a limb and the height of an individual, and anthropologists have conducted numerous studies to measure the mathematical relationship between limb length and the known height of individuals. From these studies, researchers have developed mathematical formulas for various bones which can be used to estimate height. These equations vary depending on the ancestry and gender of the individual.  For example, if you find a femur measuring 41 cm (16.14 inches) in length, then depending on the gender and ancestry of the individual, you will use one of the following equations:

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Male

Female

European

2.32 x Femur +
65.53 ±
3.94 cm

2.47 x Femur +
54.10 ±
3.72 cm

Asian

2.15 x Femur +
72.57 ±
3.80 cm

Use Male
Formula

African

2.10 x Femur +
72.22 ±
3.91 cm

2.28 x Femur +
59.76 ±
3.41 cm

In the above example, if we have
determined our skeleton is a male of African ancestry, then to calculate the
individual’s height from his femur, we would use the following calculation:

2.10 x 41 + 72.22 = 158.32 cm ±
3.91 cm (or 62.33 inches ± 1.54 inches)

Similar equations exist for
correlating height to the length of the tibia, fibula, humerus, ulna, and
radius. If you have several bones available for a given individual, you can
increase the accuracy of height estimation by applying the formulas to two or
more bones.

Next week, I’ll explain some of the
techniques forensic anthropologists use when examining skeletal remains to
determine the age of the individual at the time of death. I’ll also explore
whether it is possible to estimate the time since death from looking at
skeletal remains.

Be sure to sign up for my free mystery newsletter, and I’ll see you back here next week.

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post What Can a Skeleton Tell You? appeared first on Robin Barefield.

Bones

If you stumble across a pile of bones in the woods, can you
tell if they are human bones, and if they are human, did they belong to a male
or female? How old was he or she at the time of death? Was the individual tall
or short? What killed him or her, and how long ago did the person die?

While we might be able to identify human bones, most of us cannot answer many questions about the bones, and most of the answers elude even law enforcement officers, coroners, and trained medical examiners. Forensic anthropologists are the experts who interpret skeletal remains.

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In my latest novel, Karluk
Bones, Jane Marcus and her friends stumble across skeletal remains near
Karluk Lake on Kodiak Island. They find a skull as well as a long femur, so they
know at least some of the bones are human. The remains don’t appear to be
recent, but they also don’t look ancient, and Jane and her friends argue about
how old they might be. Jane reports the bones to the Alaska State Troopers, but
Sergeant Patterson also can’t guess at the age of the bones, so he hands them
off to a medical examiner who in turn sends them to a forensic anthropologist,
and she is able to answer some, but not all, of the questions about the bones.

I love learning, and one of the things I enjoy most about
writing fiction or non-fiction is having the opportunity to dig into a new
subject and study it not only until I understand it but until I know it well enough
to explain it to my readers. Using science to help solve the mystery of the bones
in my novel proved trickier than I expected, and Ying, my fictional anthropology
student at the University of Alaska, ended up relying on cutting-edge scientific
techniques to provide answers about the human remains Jane and her friends
found.

Beginning with this post and continuing for the next two or
three weeks, I will describe what a forensic anthropologist can deduce from bones.

Human or Non-Human

It is easy for us to recognize a human skull, and most laymen
can identify many other human bones, but if you discover skeletal remains in
the woods, human bones might be mixed with those of other animals. If a
forensic anthropologist visits the scene, she can quickly separate human from
non-human remains. If a forensic anthropologist is unavailable, then
investigators must collect all the bone scraps and send them to an
anthropologist to be sorted in the lab. Once they are in the lab, the
anthropologist cleans the bones and attempts to provide a general physical description
of the individual whose remains she is studying. The description includes:

GenderAge at DeathRace Height

The anthropologist also tries to try to determine the cause
of death as well as estimate how long ago the individual died. This week, I
will discuss how gender can be determined from bones.

Gender

The pelvis and the skull provide the most useful information
for determining the gender of the individual.

Pelvis

Females have wider pelvises to provide enough space for the birth canal, and anthropologists use several definitive measurements to differentiate the pelvis of a female from the pelvis of a male. In most cases, though, a forensic anthropologist only needs to visually examine a pelvis to determine the gender of the individual. If the pelvis is available, it is the best bony structure to confirm the sex of the person.

[image error]Male (left) Female (right)

Skull

Often, only the skull of an individual is found, but
luckily, marked differences exist between the skull of a male and the skull of
a female. An adult female’s skull remains slender and retains the smoothness of
youth, while and adult male’s skull is more robust with heavier bones and
larger muscle attachment areas. Females have a rounded forehead, while a male’s
forehead slopes back at a gentle angle. A male has a more prominent brow ridge
and square eye sockets, while a female has round eye sockets. Males have a
square jawline, and a female’s jaw is pointed.

Since individuals vary, sex determination using only the
skull is not as definitive as a confirmation made from examining the pelvis,
but the skull usually provides the anthropologist with an educated guess at the
gender of the individual.

Next week, I’ll discuss other characteristics a forensic anthropologist learns from reading bones. Meanwhile, be sure to sign up for my monthly Mystery Newsletter about true murder and mystery in Alaska.

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post Bones appeared first on Robin Barefield.

DNA Match Brings Justice for Sophie

Police have used DNA as a valuable investigative tool for the last few decades, but until recently, law enforcement agencies could only match DNA from a crime scene to a known criminal who had been convicted of a felony and forced to surrender a sample of his DNA to the national DNA criminal database. In the last few years, commercial databases have exploded in size as citizens willingly send samples of their DNA to companies such as Ancestry.com, 23andMe, and others promising to use your DNA to trace your ancestry or track genetic predispositions to diseases and conditions. Lately, when police fail to find a match in the national criminal database, they have begun submitting crime-scene DNA to commercial databases, hoping not necessarily for a direct match to an individual but for a match to a relative of their unknown suspect.

The best-known case for an arrest
based on matching crime scene DNA to an individual’s familial DNA held in a
commercial database is the April 2018 capture of Joseph James DeAngelo in
Sacramento, California. De Angelo, dubbed the “Golden State Killer,” is
believed to have committed at least 13 murders, more than 50 rapes, and over
100 burglaries in California from 1974 to 1986. When DNA held in evidence from
one of the crime scenes matched the DNA in a commercial database of a distant
relative of De Angelo, police had their first solid lead in the case in years.

When the news about the capture of
the Golden State Killer broke, I imagine detectives around the country began considering
their cold cases and wondering if they could use a similar technique with DNA they
held in evidence. Troopers in Alaska wasted no time submitting DNA from one of
the state’s best-known cold cases, and the results were no less dramatic than
those for the capture of DeAngelo in California.

[image error]Sophie Sergie

As many of you know, I write a monthly newsletter about true murder and mystery in Alaska. Several months ago, I wrote a newsletter titled, “Murder in a College Dorm,” about the 1993 brutal rape and murder of 20-year-old Sophie Sergie at the University of Alaska Fairbanks.  A janitor found Sophie’s partially-clothed body stuffed in the bathtub in a second-floor bathroom at Bartlett Hall, a dormitory on the campus of the university. Sophie had been sexually assaulted, stabbed in the face, and shot in the back of the head with a .22 caliber firearm. The murder occurred in April, just as students were taking final exams and preparing to leave campus at the end of the semester. Police interviewed as many students as possible, but the task overwhelmed them.

Police recovered DNA from Sophie’s body, but DNA processing
technology had not yet been introduced to
Alaska in 1993. In 2000, investigators uploaded the DNA collected at Sophie’s
crime scene to the FBI database but learned little other than the DNA belonged
to a male. The sample did not match anyone in the FBI’s database.

In 2010, a cold-case investigator attempted to re-interview
everyone who lived in Bartlett Hall when Sophie was
murdered, including an ex-resident named Nicholas Dazer. The
investigator asked Dazer if when he lived at the dorm, he had a gun that fired
.22-caliber ammunition. Dazer said he did not own a gun, but he recalled his
roommate, Steven Downs, had an H&R .22-caliber revolver. With little else
to go on, the case again went cold, and few people believed it would ever be
solved.

After authorities in California arrested suspect Joseph
James DeAngelo in April 2018 by obtaining a familial match from comparing DNA
collected at a crime scene to a commercially available DNA database, Alaska
State Troopers decided to try the same thing with DNA collected from Sophie’s
body in 1993. They sent the DNA from Sophie’s case to Parabon NanoLabs, the same
facility used to analyze the DNA in the Golden State Killer case. On December
18th, 2018, a forensic genealogist submitted a report comparing the
DNA from the suspect in Sophie’s case to a likely female relative. The woman
whose DNA was considered a familial match to the DNA collected from sperm left
at Sophie’s crime scene is the aunt of Steven Downs. Downs was an 18-year-old
college student living at Bartlett Hall when Sophie was murdered. Downs was also Nicholas Dazer’s roommate, the one who
owned the H&R .22-caliber revolver.

Downs was arrested at his home
in the small town of Lewiston, Maine and charged with the sexual assault and
murder of Sophie Sergie. He denied any involvement in Sophie’s rape and murder,
despite the fact a specimen of his DNA taken after his arrest matched a sample
collected from sperm cells at the crime scene. His attorney said Downs would
not waive his rights and did not agree to be
extradited to Alaska. Downs is currently being
held without bail in an Auburn, Maine prison until his next court hearing when Alaskan authorities expect to
escort him back to Fairbanks to stand trial.

Will Sophie finally receive
justice?

If you would like to receive updates on Sophie’s case as well as learn about other murders and mysteries in Alaska, please sign up below for my monthly Mystery Newsletter.

________________________________________________________________________

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post DNA Match Brings Justice for Sophie appeared first on Robin Barefield.

Marine Reserves for Rockfish

Should fisheries managers implement marine reserves to
protect fragile rockfish populations? This week, I’ll tackle the controversial
subject of marine reserves. What are they; do they work; and should they be employed
to protect rockfish populations and help already depleted populations recover?

Two weeks ago, I discussed rockfish conservation, and last week, I explained how to implement the deep-water release technique for rockfish. If you missed either of those two posts, I suggest you read them to understand the biology and physiology of rockfish and why rockfish populations are fragile and subject to overfishing.

Marine reserves have been
developed in certain areas where rockfish have been over-harvested.
Before I start discussing the pros and cons of marine reserves, though, I want
to differentiate between a few ecological terms I find confusing.

Marine Protected Area (MPA): This broad term covers a variety of management areas, including marine sanctuaries, estuarine research reserves, ocean parks, and marine wildlife refuges. Some MPAs are established to protect ecosystems, while others preserve cultural resources such as shipwrecks and archaeological sites, and still others are established to sustain fisheries production. Nearly all MPAs in the United States allow a variety of human activities, including fishing.

Marine Reserve: A Marine Reserve is a special, restrictive type of MPA where either no or only limited fishing (sport or commercial) and development are allowed. Marine Reserves are sometimes further divided into “Marine Reserves,” and “No-Take Marine Reserves.” When used together, these two terms usually mean managers allow some fishing for certain species in a Marine Reserve but place a ban on all fishing in a No-Take Marine Reserve.

When you add terms such as Marine Parks, Marine Preserves,
and National Marine Sanctuaries to the mix, you end up scratching your head,
wondering what each designation means. In this post, when I discuss marine
reserves, I am talking about the implementation of a distinct area closed to all fishing.

Fisheries managers in the eastern North Pacific have
designated several marine reserves in critical rockfish habitat where rockfish
have been overfished. By prohibiting fishing
in these areas, managers hope to rebuild overfished populations and protect
spawning and nursery habitat. By closing an area to all fishing, biologists can
protect rockfish not only from anglers who target rockfish but also from
anglers who fish for other species and harvest rockfish as by-catch.

Fishermen generally do
not like marine reserves because they lose fishing areas. Reserves protecting
rockfish are also controversial because studies suggest as much as 20% of
rockfish habitat would have to be closed
for a reserve to be effective. Also, reserves displace effort and place
pressure on open areas.

Some reserves appear to have benefitted local rockfish
populations, but biologists are still uncertain about the overall success of
reserves for managing rockfish. Since rockfish do not reproduce until they are
several years old, though, and since few larvae survive to reach adulthood, it could
take years to realize the benefits of rockfish reserves. Are we willing to wait
before we judge the efficacy of these protected areas?

I planned to write two posts on rockfish and ended up writing six. The more I learned about these interesting fish, the more questions I had. I hope I found a few readers who are as intrigued by rockfish as I am. Before tackling my next group of fish, I’ll write a few posts on other topics.

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Thank you for visiting my website, and don’t forget to sign up for my Mystery Newsletter!

____________________________________________________________________________

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post Marine Reserves for Rockfish appeared first on Robin Barefield.

Deepwater-Release Technique for Rockfish

This week, I ‘ll describe the deepwater-release technique developed for rockfish. In my last post, I wrote about rockfish conservation and talked about ways anglers can help preserve vulnerable rockfish populations. Due to their unvented swim bladder, rockfish are extremely sensitive to changes in water pressure. When an angler catches a rockfish in water deeper than 90 ft. (27.43 m) and reels it to the surface, the fish’s swim bladder rapidly expands, compressing internal organs and often pushing the stomach out through the mouth. These pressure change can also rupture blood vessels, tear the swim bladder, and cause bulging eyes or gas bubbles in the eyes.

[image error]Distressed Rockfish

Sometimes rapid pressure changes cause physiological damage so severe it kills the fish, but in other instances, the fish can survive if the angler quickly returns it to the depth where it was caught.

Since a rockfish’s swim bladder rarely deflates on its own
once the fish arrives at the surface, the fish cannot dive and instead floats until
it dies or is eaten. Anglers sometimes mistakenly feel they can help the
fish by either puncturing the stomach protruding from the fish’s mouth or
puncturing the fish’s body to let air out of the swim bladder. This technique, called
“fizzing” or “venting,” often leads to infection and eventual death.

[image error]Deepwater-Release Devices

Recently, biologists have developed a new deepwater-release
technique to submerge rockfish as quickly as possible either to the depth where
they were caught or 100 feet (30.5 m),
whichever comes first. Research on this technique has shown a substantial
increase in the survival of released rockfish. One laboratory study produced a
survival rate of 96% for recompressed rockfish. Another study in the wild found
only 22% of yelloweye rockfish released at the water’s surface managed to
submerge, but 98% of yelloweyes survived when submerged to the depth where they
were captured.

The Alaska Department of Fish and Game has now added the deepwater-release technique to its list of
“best practices” for anglers to employ to minimize release mortality of
rockfish. Biologists believe if they can convince anglers to use this technique,
as well as follow other rockfish conservation methods, rockfish mortality will
decrease significantly.

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What is the deepwater-release technique? It is a simple
procedure, but since time is critical, rockfish anglers should have the gear
ready and be prepared to implement the technique as soon as the rockfish
arrives at the surface.

Several deepwater-release devices, from simple to sophisticated, can be purchased, but you can also easily make your own deepwater-release device. Begin with a 3-lb. jig with a single hook and grind the barb off the hook. Next, take a fishing rod and attach the line to the bend of the hook. Assemble the device and have it ready to go before you start fishing. The fish is much more likely to survive if you minimize its time at the surface, so have the device assembled and make sure you know what to do before you catch a rockfish.

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If you think you have a rockfish on the line, quickly reel the fish to the surface. The swim bladder will inflate regardless of your reeling speed. Remove the hook from the fish’s mouth and attach the release device. If using a homemade device, hook the barbless hook through the soft tissue of the jaw. Gently drop the fish back into the water and release the anti-reverse on the reel, allowing the line to free spool. Allow the fish to descend until either the jig hits bottom, or reaches 100 ft., whichever comes first. Then, give the rod a hard tug to release the fish. The faster you can perform this technique, the more likely the rockfish will survive.

Next week, I’ll discuss marine reserves as a possible management option to protect rockfish populations. Reserves are controversial because both sport and commercial fishing are prohibited in reserves, and many biologists question if reserves work as a form of conservation.

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Be sure to sign up for my free, monthly newsletter about murder and mystery in Alaska!

y the way, Mary Ann’s books would make perfect Christmas presents!

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post Deepwater-Release Technique for Rockfish appeared first on Robin Barefield.

Rockfish Conservation

This week, I want to discuss rockfish conservation. Over the past few weeks, I’ve discussed how rockfish are more vulnerable to overfishing than most species of fish, and non-pelagic rockfish populations are particularly fragile. Rockfish prefer rocky habitats where anglers can easily find and target them, and rockfish are quick to take a lure, making them easy to catch. Also, they grow quickly but mature slowly, so they are often caught before they can reproduce and sustain their population. It is their physiology, though, not their lifestyle which makes rockfish susceptible to annihilation by anglers.

[image error]Stomach protruding from mouth

Rockfish rarely survive catch-and-release fishing because
they have an unvented swim bladder. The swim bladder is a balloon-like organ which
adjusts the buoyancy of a fish. As the fish ascends toward the surface, the
swim bladder inflates. If the swim bladder has a vent, it can easily again deflate
when the fish dives, but a rockfish cannot quickly deflate its swim bladder,
and since the fish normally remains in deep water, it has no need to make large
adjustments in the inflation or deflation of its bladder. When an angler
catches a rockfish, though, and reels it to the surface, the gasses in the swim
bladder expand and compress internal organs. Often, by the time the fish
reaches the surface, the stomach bulges into the mouth cavity. Other common pressure-change
injuries include ruptured swim bladders, ruptured blood vessels in internal
organs, and bulging eyes or gas bubbles in the eyes.

Once the swim bladder of a rockfish has completely expanded,
it will not likely deflate on its own because it does not have a vent. If the angler releases a fish with an
inflated swim bladder, the fish floats on the surface until it suffocates, or
something eats it. Gulls often land near floating fish and peck out its eyes while
the fish is still alive.

Rockfish are good to eat and are harvested in commercial, sport, and subsistence fisheries from California to Alaska. Anglers have depleted many rockfish populations from British Columbia to California, and even when fisheries managers enact strict regulations or completely ban fishing in certain areas, these populations are slow to recover. Only older rockfish can reproduce, and few rockfish larvae survive to reach maturity.

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Rockfish are not easy to manage because they live in deep,
rocky spots where biologists cannot employ traditional sampling techniques. In
Alaska, researchers do not know the abundance of most rockfish stocks, so
fisheries managers have elected to implement strict regulations for catching
and retaining rockfish, especially for yelloweye and other non-pelagic
rockfish. Since even the rockfish anglers release are likely to die, though, biologists
now focus on informing anglers of the fragility of rockfish populations.

The Alaska Department of Fish and Game distributes
literature to sportfishing guides and posts informational signs near boat ramps
to encourage anglers to follow these guidelines to avoid catching rockfish or
to at least minimize rockfish harvest.

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If you are not targeting rockfish, avoid fishing
where you are likely to catch them. Rockfish inhabit the steep sides of rock
piles and reefs. Lingcod are found at the
top of rock piles and reefs, and halibut
lie on the flat bottom near a reef.If you are targeting lingcod or halibut, keep
your jig 10-15 ft. (3-5 m) off the
bottom. Researchers in Oregon found this technique significantly reduced
rockfish bycatch but did not affect the odds of catching halibut and actually increased the success rate for landing
lingcod.If you want to retain a few rockfish along with
other species, target the other species first and retain any incidental
rockfish you catch.Fish with a circle hook. Circle hooks stick in
the mouth and are not ingested, so they
are easier to release and less likely to cause a serious injury.Remember, rockfish only have a freezer life of
four months, so don’t catch more than you can eat. If targeting rockfish, implement deep-water-release
methods.

In my next post, I will discuss deep-water-release techniques in more detail. This simple concept produces surprisingly successful results.

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Several weeks ago, I mentioned the Reader’s and Writer’s Book Club started by my publisher and some of my fellow authors. You can still claim your free lifetime membership to the club by following this link, but free membership will end within the next few weeks. I am currently writing a mystery with the aid of club members, and I invite you to join the fun!

As always, thanks for visiting my blog, and don’t forget to sign up for my free monthly mystery newsletter about true murder and mystery in Alaska.

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post Rockfish Conservation appeared first on Robin Barefield.

Black Rockfish

Black rockfish (Sebastes melonops) range from range from Amchitka Island, Alaska in the Aleutian Islands to California. Two weeks ago, I wrote about rockfish in Alaska, and I explained that biologists classify rockfish by dividing them into two groups: pelagic and non-pelagic. Last week, I wrote about yelloweye rockfish, a non-pelagic species. This week, I’ll write about black rockfish, a pelagic species and the most common rockfish in Alaskan waters.

Although not related to the bass family, anglers often refer
to black rockfish as black bass because their shape resembles a bass. They have
a mottled gray-black body, usually with dark stripes extending from the head to
the gill cover. The sides are lighter than the back, and the stomach is pale
gray. Black rockfish have a large mouth and a spiny dorsal fin. As with other
rockfish, venom sacs lie at the base of each spine. The venom is only mildly
toxic to humans, but it does cause pain and can lead to infection. Their
light-colored stomach, the lack of pores or a knob on the lower jaw, black
mottling on the dorsal fin, and their large mouth
which extends past their eyes, are all features which distinguish black
rockfish from similar species such as dark rockfish and dusky rockfish. Black
rockfish grow to a maximum length of 29.6 inches (69 cm) and weigh up to 11
lbs. (5 kg).

Black rockfish are found anywhere from the surface to 1200
ft. (366 m) deep, but they usually inhabit water shallower than 492 ft. (150
m). They are sometimes seen in large schools at the surface when they are
feeding, but they most commonly occur in rocky areas or remain above rocky
pinnacles.

Black rockfish are much more mobile than yelloweye rockfish,
but biologists in Oregon performed a tagging study and learned the average home
range of a black rockfish is only .2 square miles (.55 sq. km). A rockfish
sometimes travels outside its home range
during the reproductive season or to feed.

[image error]Black Rockfish

Black rockfish reach sexual maturity between the ages of six
and eight years. After mating, the female stores the male’s sperm for several
months before fertilizing her eggs. Then, between January and May, she releases
between 125,000 and 1,200,000 larvae. Black rockfish have a maximum lifespan of
fifty years.

Black rockfish feed on zooplankton, crab larvae, and small
fish species such as herring and sand lance. Predators of rockfish include
sablefish, halibut, other fish species, and seabirds such as pigeon guillemots.

Black rockfish populations in Alaska are considered stable,
but fisheries managers set conservative limits on all species of rockfish.
Because black rockfish grow and mature slowly,
live nearshore, and have small home ranges, they are susceptible to overfishing
by sport and commercial fishermen. They
are easy to find and easy to catch. Like other rockfish species, they have an
unvented swim bladder, and when anglers reel them to the surface, they usually
do not survive if released.

As I have mentioned several times over the past few posts, both pelagic and non-pelagic rockfish are highly susceptible to barotrauma, physical injuries due to rapid changes in pressure when an angler catches a rockfish and brings it to the surface. In my next post, I will discuss ways to spare rockfish from barotrauma and methods to protect fragile rockfish populations.

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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L

The post Black Rockfish appeared first on Robin Barefield.

Yelloweye Rockfish (Sebastes ruberrimus)

The brightly colored yelloweye rockfish looks like a fish
you might expect to see swimming near a tropical reef, but yelloweyes live in the frigid waters of the
northeastern Pacific Ocean, from Baja California to the Aleutian Islands in
Alaska. Anglers sometimes call yelloweyes red snapper, but they are not
snappers and are not related to the red snappers found in the Gulf of Mexico.

Yelloweyes are among the largest rockfish found in Alaska and can grow to 36 inches (91.44 cm) in length and weigh 24 lbs. (11 kg.). They vary in color from orange-yellow to orange-red, and they tend to become more yellow as they age. Juveniles are usually bright red and have two vertical stripes, one above and one below the lateral line. As they age, the stripes fade, and their color changes to a red-orange or orange. A very old rockfish might be yellow. While their fins tips of adults are usually black, the fins of juveniles are tipped either white or black. As their name suggests, their eyes gleam bright yellow, making them easy to identify. In addition to the spines found in their dorsal and anal fins, several small spines sprout from their head.

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Adult yelloweyes are solitary fish and live in steep, rocky
areas, where they can find shelter. They typically live on the ocean bottom,
and they don’t venture far from their rocky homes. They usually live between
300 and 600 ft. (91.44 – 182.88 m), but they have been found in only 48 ft.
(14.63 m) of water and as deep as 1,800 ft. (548.64 m). Because yelloweyes live
in rocky areas near the bottom and have small ranges, biologists classify them
as one of the species of non-pelagic rockfish.

Rockfish are long-lived and slow to mature. Yelloweyes can live over 100 years, and the oldest recorded was a 121-year-old individual caught in Southeast Alaska. Yelloweye males mature when they are approximately 18-years-old, while females do not reach sexual maturity until 22-years of age. Males fertilize a female’s eggs internally, and the female then carries and nourishes the eggs until they hatch into larvae. One female can give birth to as many as 2,700,00 larvae.

Since the female nourishes
her eggs and gives birth to live organisms, you might expect rockfish to have a
higher reproductive success rate than do other fish species where eggs receive
little or no parental care, but unfortunately, only a small percentage of
rockfish larvae survive to adulthood, and
even fewer survive until they are sexually mature. As soon as they are
released, ocean currents sweep most of the larvae out to sea, and the young fish die before they have a
chance to feed and grow. Other larvae starve to death from a lack of food,
while many fall prey to larger fish, seabirds,
and other organisms. The few larvae that survive,
drift with the ocean currents while they eat and grow into small fish.
They then settle to the bottom where they can find protection from predators
among rocks and under kelp. As the young grow, they move into deeper water.

Yelloweye populations are fragile and vulnerable to
overfishing. Females do not reproduce until they are over twenty-years-old, and
once the female releases her larvae, few of the young survive. Recruitment of
young fish into the population is slow, and if a fish reaches sexual maturity
and is then caught by an angler or eaten by a predator, the population suffers
not only the loss of this one individual
but also the loss of all the potential young this one fish could have produced
during its long life.

Because yelloweyes seldom move from one area to another,
they are easy targets for anglers, and they are easy to catch. Even strict
regulations which prevent the retention of non-pelagic rockfish do not protect
yelloweyes because when an angler reels a yelloweye to the surface from a depth
greater than 90 ft., the fish usually cannot return to the bottom, and when
released, it floats at the surface until it dies. Yelloweyes, like other rockfish,
have an un-vented swim bladder, and as the swim bladder inflates when the fish is reeled to the surface, it compresses
internal organs and often pushes the stomach out of the mouth. The fish cannot
deflate its swim bladder at the surface, but the swim bladder will deflate to
the normal size if the angler can return the fish to the bottom where it was caught. New deep-water release techniques
have helped improve the survivability of released rockfish.

The best way to avoid killing a yelloweye is to avoid fishing in the rocky areas where they live. Fisheries biologists find it difficult and expensive to manage non-pelagic rockfish because hauling them to the surface to tag them would likely kill them. Researchers believe most yelloweye populations in Alaska remain stable, but they’ve enacted strict regulations to protect these beautiful fish.

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post Yelloweye Rockfish (Sebastes ruberrimus) appeared first on Robin Barefield.

Rockfish of Alaska

Scientists have identified more than 102 species of rockfish belonging to the genus Sebastes, and over thirty species live in Alaskan waters.] Although anglers sometimes refer to yelloweye rockfish as red snapper, and many call black rockfish black bass, there are no snapper or bass in Alaska.

Rockfish belong to the family Scorpaenidae, the “scorpionfishes.” Scorpionfish have venomous spines in their fins, and the venom in some species is extremely toxic. Rockfish venom is only mildly toxic, but it causes pain and swelling and can lead to infection. In most species of rockfish, the venom sacs are located at the base of the dorsal and anal fin spines, but in a few species, other fin spines are also venomous. They use their venom to defend themselves.

A rockfish has large scales, and in addition to its  fin spines, it has smaller spines on its head and gill covers. Species range in color from bright reddish orange and yellow to gray and black. Individuals of some species grow to 40 inches (101.6 cm) in length.

[image error]Black Rockfish

Scientists divide rockfish species into two groups based upon their preferred habitats: Pelagic and Non-Pelagic. Pelagic species can be found at any depth and usually swim in large schools above rocky shelves. Pelagic species include black, dusky, dark, and yellowtail. Solitary non-pelagic rockfish remain near the bottom in rocky areas, sometimes hiding in cracks or under rocks. They usually live at a greater depth than pelagic species. Non-pelagic species include yelloweye, tiger, quillback, silvergray, China, copper, rougheye , and shortraker. 

Rockfish are some of the longest living vertebrates. A yelloweye caught in Southeast Alaska was 121 years old, and shortraker rockfish can live over 150 years.]

Some species of rockfish reach sexual maturity at five to seven years old, but others do not begin to reproduce until they 15 to 20 years of age. Most fish lay and fertilize eggs externally, but rockfish mate internally, and the female carries and nourishes the eggs for several months before giving birth to thousands or even millions of tiny larvae. The larvae are at the mercy of the ocean currents and wind, and most get swept out to sea and don’t survive. Those that do survive, are subject to predation. The larvae feed and grow in the ocean column for several months before they settle onto the ocean floor where they can seek protection in the kelp and rocks. As the young mature, they move into deeper water.

Researchers have found that while pelagic rockfish sometimes travel hundreds of miles, most maintain a range of only twenty miles. Non-pelagic species have very small ranges of only a few-hundred yards, and some spend their entire lives on the same rock pile.] Because non-pelagic species do not travel far from their rocky homes, they are easy targets for anglers and are vulnerable to overfishing.

Rockfish eat plankton, crabs, shrimp, and small fish, including smaller rockfish. They are preyed upon by Pacific cod, lingcod, sablefish, other rockfish, halibut, king salmon, sculpins, sharks, seabirds, marine mammals, and humans.

Non-pelagic rockfish are more susceptible to overfishing than most fish species. Not only are they easy to find and catch, but they rarely survive catch-and-release fishing because their air bladder or swim bladder has no vent. A fish uses its swim bladder to adjust buoyancy, and when a rockfish is caught in its deep home and reeled to the surface, the balloon-like swim bladder rapidly expands and pushes against its internal organs. By the time the fish reaches the surface, the expanded swim bladder often shoves the stomach into the mouth. Once it is at the surface, the fish is unable to deflate the swim bladder, and if the angler releases it, the fish will float at the surface and die.

[image error]Rockfish at the Surface

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In my next post, I will discuss yelloweye rockfish in more detail, and in the following post I’ll focus on black rockfish. Then, I’ll talk about rockfish management and techniques anglers can employ to preserve non-pelagic rockfish populations.

I have been traveling for the past two weeks and will be on the road for another three weeks, so my posts have been less frequent than usual, and I probably won’t return to a steady schedule until I get home. Thanks for reading, and I hope you are enjoying a great winter.

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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The post Rockfish of Alaska appeared first on Robin Barefield.

Happy New Year 2019

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Happy New Year! Time flies, doesn’t it? I feel as if I just
wrote my 2018 New Year’s post. Since I post my resolutions on my blog, I can’t
pretend at the end of the year to forget what resolutions I made in January. A
quick look back at last year’s post reminded me I did not finish as many
writing projects as I’d planned.

I work hard to be a successful author, but as an author, I
must wear many hats. On my best days, I’m able to sit down and work on my
novel, and on my worst days, I spend my time promoting my books, my website, or
my mystery newsletters. I couldn’t have known a year ago how much time I would
spend in the coming year working on promotion and on building my author platform,
and the more time I spend on promotion, the less time I have available to
write. It’s a trade-off, and usually, I choose writing, but during the last few
months, I decided to get serious about my author business.

Although my next novel, Karluk Bones,
is not yet ready to send to my publisher, I finished the rough draft this past
week. I resolve to send Karluk Bones to my publisher by late spring and have it
in the hands of readers by late summer or early fall. I know how long it takes
to edit and publish a novel, so this seems like a reasonable resolution.

My second resolution is a promise to
myself to finish editing my wildlife book and get it published and to market by
the end of the year. I made this same resolution last year and didn’t accomplish it, but I hope 2019 will be different. My wildlife book requires
extra time and energy in every facet of the writing and editing process. I know
the book will never be perfect, but I want to do the best job I can on it, and
I hope it will be worth the wait.

Karluk Bones and The Wildlife of
Kodiak Island will be my two be my two main writing projects for 2019, but I
hope to begin my next novel sometime this coming spring or summer. I already have
a rough idea for the plot, and I would love to start writing it now. My next
planned non-fiction book will be a compilation of my true stories of murder
from Alaska. These are the tales I write every month for my Mystery Newsletter,
and I have more than enough compiled for a book.

I’d better stop before I promise too
much. I plan to remain active in The Reader’s and Writer’s Book Club, and I
hope to write more articles for True Crime: Case Files and Medium. I also want
to leave enough time in my schedule to explore other opportunities I discover.

I haven’t written a wildlife post in
several weeks, but I’m returning to fish and will write about rockfish over the
next few weeks.  Thank you for reading my
posts this past year, and I hope you will stay with me through 2019.

Happy New Year, I wish you health, happiness, and prosperity!

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Robin Barefield is the author of three Alaska wilderness mystery novels, Big Game, Murder Over Kodiak, and The Fisherman’s Daughter. To download a free copy of one of her novels, watch her webinar about how she became an author and why she writes Alaska wilderness mysteries. Also, sign up below to subscribe to her free, monthly newsletter on true murder and mystery in Alaska.

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Mystery NewsletterSign Up for my free, monthly Mystery Newsletter about true crime in Alaska.





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The post Happy New Year 2019 appeared first on Robin Barefield.