The Last of its Kind Sharks throughout the world are being destroyed at a devastating rate for shark fin soup and other human causes. This image of a lonely reef shark cruising over a desert of sand was captured to help portray the importance of conservation before we lose them FOREVER. Photo by Laz Ruda.
Unfortunately, the sea otter’s remarkable fur has also been the main source of its troubles. Once known as the “sea beaver” because of the value and economic importance of its pelt, sea otters were hunted throughout their range by multiple nations beginning in the 18th century when a crew of Russian sailors discovered sea otters while shipwrecked in the Commander Islands. By the beginning of the 20th century, a single sea otter pelt was worth over a thousand dollars. By that same time, perhaps only 1000 to 2000 otters remained in the wild, and fear of their extinction led Russian, Canada, the US, and Japan, to sign a treaty outlawing the trade in otter fur. Now, only indigenous peoples of the United States are allowed to hunt sea otters, and the resulting rebound of the population has been considered one of the greatest successes in the history of marine conservation.
You own more field clothes than professional clothes.
Your Keens are your most valuable pair of shoes.
You probably own a wetsuit for every kind of weather and water temperature (guilty, I own 5 wetsuits and a hoodie…).
You shake your head when you tell people you work in marine science and they say “so are you a dolphin trainer?”
The only fashion trends you care about are new scuba diving equipment.
You go full-on nerd when you can access a scientific paper for free.
You also go full-on nerd when your research gets published for the first time.
Statistics are your living nightmares.
Grants, grants, grants, grants…. grants!
You have an irrational obsession with the Cousteau family, Sylvia Earle and/or David Attenborough.
It’s very hard for you not to buy everything you see at the store that is ocean-related or that has a marine animal on it.
You get to spend time at sea or on remote islands with no access to the outside world or the Internet and actually enjoy it.
Chances are, you’ve been stung by fire coral, jellyfish multiple times, have had some urchin spines stuck in your leg, got bitten by damselfish or got weird rashes from who knows what was in the water?!
You often communicate using dive signs with your co-workers, even though you’re on land.
The sound of a biogeochemistry class doesn’t scare you away.
You usually have one favorite ocean species and get very fired up when people start arguing with you about it.
You have watched Blue Planet at least 20 times.
And The Life Aquatic with Steve Zissou.
Similarly, you know every line from Finding Nemo.
You have inadvertently brought back wildlife home from the field, and only realized when you saw a little crab crawling around your bathroom floor.
You already have, or are seriously considering getting tattoos related to the marine life.
You get ridiculous tan lines in the summer doing field work.
One of your most acute fear is that something will get messed up in your tanks and will kill your live animals, i.e killing your dreams of a thesis.
You have gone multiple days without a shower, and sometimes you’ve had to resort to a saltwater shower.
As a lady, your coworker are used to seeing you ‘au naturel’, because really, ain’t nobody got time for make-up while you’re in the field.
You think you are going to change the world… hey, maybe you will ;)
In the absence of normal cardioversion resources, would it be possible and/or useful to lower someone's heart rate by ducking their face in cold water (i.e. activating the dive reflex)?
Yes, but only for one specific circumstance (and maybe not exactly how you’re thinking).
May I introduce you to my favorite arrhythmia: Paroxysmal Supraventricular Tachycardia (PSVT). I like it because its not too deadly, can be utterly terrifying, and there’s a lot of cool ways to treat it. One of the more common first line treatments for PSVT is the use of a vagal maneuver, one of which involves dunking one’s head in ice water.
There’s a lot of background I have to go through to explain it though, so bear with me:
Heart Electrical Stuff:
The heart rate and rhythm are controlled by structures in the heart capable of sending electrical signals (pacemaker nodes). When those nodes send out an electrical signal, it travels through the heart muscle across specialized fibers. As the electrical signal passes them, cells that are sensitive to that signal contract in sequence. This results in a coordinated beat.
If this electrical signal is discharged inappropriately or interrupted, the result is an abnormal heart beat, rate, or rhythm. Some of these abnormal heart beats, rates, and rhythms, especially ones that start in the lower part of the heart (the ventricles) can be deadly.
Fortunately, PSVT starts in the upper part of the heart (the atria), and is not deadly on its own. It occurs when one of the pacemaker nodes in the upper part of the heart (the SA or AV node) get “stuck” discharging signals too fast- sometimes as many as 250 times per minute.
Even though this likely won’t kill the person, it’s still a problem because when the heart beats too fast, it does not have time to completely fill with blood in between beats. This means not enough blood gets out to the body and brain, causing dizziness and shortness of breath (because enough oxygenated blood isn’t getting to the brain and body tissues, causing a slight lack of oxygen throughout the body). Some people can feel their heart beating abnormally fast, and some have chest pain with this too.
Treating PSVT (what you’re actually here for):
One of the first ways to treat PSVT is the use of vagal maneuvers.
Vagal maneuvers are different actions that can stimulate the vagus nerve- a nerve that connects the heart and lungs to the brain. When triggered, the vagus nerve releases neurotransmitters that can slow the heart rate set by the SA and AV nodes. In the case of PSVT, this might be enough to “break” the ultra fast heart rate and reset to a normal one.
Some vagal maneuvers include:
Bearing down (as though trying to poop)
Carotid massage (massaging the area of the carotid artery just below the jaw- this should only be done by trained professionals, though, as a last resort before moving on to more invasive treatment)
Submerging the face/head in ice water
See, told you we’d actually get to this. The dive reflex (which I should really do a whole post about, cause its super cool, uh, literally) is a trait that allows aquatic mammals to conserve oxygen and stay under water longer by significantly decreasing their heart rate and shunting blood into their core. Hitting one of the nerves in the face (the trigeminal nerve) with freezing water mimics this reflex in humans, which in turn triggers the vagus nerve, which is what helps treat the PSVT. Here’s my favorite PSVT home video about vagal maneuvers.
Just for funsies, I’m going to keep going. If vagal maneuvers are ineffective, the next step up is to use a medication called adenosine. Adenosine is given IV, where it is pushed as fast as possible into the vein. When it hits the heart, it briefly stops it. The hope is that it starts back up in a normal rate. Think chemical defibrillation. Here’s another one of my favorite PSVT video about adenosine administration.
People can have episodes of PSVT frequently or just once or twice in their whole lives. If it becomes a problem, certain parts of the heart can be cauterized to prevent future attacks.
Personal note: I’ve had four runs of SVT in my life, the longest one
lasting a little over an hour. All were eventually treated with vagal
maneuvers and I never had to be hit with adenosine or cardioversion, but if I ever do, I’ll certainly share my experience with you all.
Sand dollars are flattened and disk-shaped and have five rows of tube feet which allow for extremely slow locomotion. The narrow elongated holes in the sand dollar test (shell) are lunules, which serve as channels to help move food from the aboral surface to the oral surface and the mouth.
Check Out the Close Ups of Coho Spawning on the Salmon River - taken in November while conducting a coho spawning survey on the Salmon River in northwest Oregon.
The rivers, streams, and lakes of Oregon and Washington are home to a diverse array of fish species, and the BLM is committed to the restoration and protection of the aquatic habitat the fish are dependent on.
Salmon and trout species found on BLM-managed lands include bull trout, westslope cutthroat trout, Yellowstone cutthroat trout, Lahontan cutthroat trout, redband trout, steelhead trout, and chinook and sockeye salmon. Five of these species (bull trout, Lahontan cutthroat trout, steelhead trout, chinook salmon, and sockeye salmon) are on the Endangered Species Act list in all or portions of their distribution.
The BLM addresses the management of fish and their habitat in District Resource Management Plans and through such initiatives as the Northwest Forest Plan, PACFISH and InFish. The BLM is also a member of the Federal Caucus, which is a group of nine federal agencies with management responsibilities for listed fish species. The Caucus works together to improve interagency coordination and management of all the factors that influence fish survival: habitat, hatcheries, harvest, and hydropower operations.
Giant Salamander As Big As a Dog National Geographic
Giant salamanders can grow to 5 feet in length and weigh up to 80 lbs.
They face a barrier of dams in Japan, built to control flooding. Now
it’s hoped a new system will help these giant amphibians get upstream
past the dams to lay their eggs.