New paper: feeding ecology of South Florida sharks

We have a new paper out today in the journal Aquatic Ecology! Read it here, open access copy here. This is the last paper from my Ph.D. dissertation, and coauthors include my Ph.D. advisor Dr. Neil Hammerschlag, Ph.D. committee member Dr. Mike Heithaus, and colleague Dr. Les Kaufman. It’s called “Intraspecific Differences in Relative Isotopic Niche Area and Overlap of Co-occurring Sharks,” which I think rolls right off the tongue and would make a pretty sweet band name. This research was crowdfunded by the SciFund challenge a few years ago, so thanks again for your support! I want to tell you a little bit about what we did and what we found!

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All the times gender bias has reared its ugly head

Maybe it’s because I’m actually intimidating, but I for the most part consider myself fairly lucky as a woman in science. I’ve been fortunate enough to escape the horror stories of exploitation and sexual harassment that fill many of my colleagues’ journals. Yet, the recent story about the lack of medium-sized spacesuits – and the social media chatter about lack of women’s field gear – hit a nerve. It made me question my perceived luck.

I also remembered reading other women’s long list of times gender bias reared its ugly head in a career perfectly devoid of major sexual misconduct. I bet I could write that, I thought to myself. I wonder how long the list would be. So here goes, starting with the most egregious:

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30 Earth Month Heroes

Earth Month Heroes Narrissa Spies, Edz Villagomez, Sylvia Earle, and Charlotte Vick.

Earth Day is April 22, which makes next month Earth Month.

I’d like to invite you to participate in a Twitter hashtag campaign for the entire month.  The purpose of this campaign is to bring some attention and praise to the people who are doing great conservation work.  I’m calling the campaign #30EarthMonthHeroes.

Participation is easy.  Starting on April 1, post a tweet about someone who you think is doing great work to protect the Earth or the Ocean, either someone you know or someone you would like to know. Say something nice, upload a photo, link to a story or a video, tag them, and use the hashtag #30EarthMonthHeroes. 

Each subsequent day, thread one additional tweet about someone you admire.  It’s important to thread your tweets, so that by the time you get to April 30, you will have one single long thread.  If you thread them properly, throughout the month, as readers find your tweets they will be able to easily scroll up and down to find the people that you’ve been tweeting about.  If this works the way I hope it will, even the people who find your tweets as late as April 30, will still be scrolling back to your tweets from April 1. 

If all goes according to plan, we reach new audiences on a large scale and greatly impact the conversation about conservation, while building a twitter following for ourselves, as well as the people who we call out as Earth Month Heroes. Plus it’s nice to hear from your colleagues when you are doing a good job.

It’s really that simple. 

This is meant to be voluntary and fun, and it’s a chance to say thanks to the people in our line of work who dedicate their lives to making the world a better place – so no pressure!

If you have any questions, please ask them in the comments section and I will try to answer them.

How do I thread my tweets?

Ask Twitter.

Does my Ocean Month Hero need to be on Twitter?

If you are picking 30 people that inspire you, chances are one or more are not going to be on Twitter.  Don’t let that stop you from recognizing them!  If you can’t tag them, you could try adding a link to their website or to something they wrote.

Does my Ocean Month Hero need to be alive today?

Again, you should recognize whoever you want.  I’ll be shocked if Rob Stewart and Ruth Gates don’t get a few mentions (I’m going to mention Rob, whose final film Sharkwater: Extinction comes out on Amazon Prime on April 22), and won’t be surprised if the likes of Henry David Thoreau or Rachel Carson pop up.

What if I need to miss a day?  Or a week?

That’s fine.  The idea is to post one Ocean Month Hero per day, but if you can’t post over the weekend, post three on Monday.  And if you only get to 14 over the course of the month, those 14 people will still be happy to be recognized by you.

With no Blue Book for program guidance, Congress will hold its first hearing on Defunding NOAA, today.

At 10:15 AM, the House Appropriations Committee will meet to discuss The National Oceanic and Atmospheric Administration’s Budget Request for Fiscal Year 2020, an aggressively uninspired document that fundamentally dismantles America’s premier ocean and climate research agency and will cause immeasurable destruction to out coastal communities and economies.

You can watch the hearing live, here: https://appropriations.house.gov/legislation/hearings/the-national-oceanic-and-atmospheric-administration-s-budget-request-for-fiscal

Curiously, Commerce has not released the Blue Book, a guiding document that outlines the specifics of how the new budget will impact each program within NOAA. To my knowledge, this is the first time these hearings have commenced without these guiding documents, making it impossible for the American people to understand what, exactly, is at stake if Secretary Ross pushes his anti-science and anti-ocean budget through.

We’ll be watching.

Fun Science FRIEDay – Life is Inevitable

Why does life exist? Its an age old question that has been debated for centuries with popular hypotheses crediting celestial interference, a primordial soup, or a colossal stroke of luck. However, a relatively recent and provocative hypothesis suggests luck has nothing to do with it, and that instead, life is an inevitable consequence of physics.

The author of the concept, Jeremy England – professor of biophysics at MIT, suggests, “the origin and subsequent evolution of life follow from the fundamental laws of nature and should be as unsurprising as rocks rolling downhill.”

 

(Photo credit: creative-bioarray)

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Why I don’t bite everyone that stresses me out: The cost-benefit analysis of predators

There is controversy whenever a human creates a close interaction with a wild animal.  Those arguing in favour of the human’s behavior inevitably settle on the argument that if the animal didn’t like it, the animal would have bit them or exhibited some sudden reaction to the human.  People who propose this argument have a very limited understanding of animal behavior.

Real talk, I used to believe this totally incorrect argument, and I will never forget the day that changed my perspective forever.  I was a budding zoologist working on a remote island with a group of scientists that were ringing cormorants.  The cormorants squawked for awhile, but then got “used” to our presence and calmed down.  I was reassured that we weren’t causing them any distress as we worked nearby, otherwise I expected that they would have shown it by either continuing to squawk or simply fly away.  Then, I noticed a few dead cormorants near where we worked.  I thought that they must have died before we arrived.  However, the senior researcher explained that they had been alive moments before but most likely died due to the stress of our presence.  That was an extremely powerful lesson in my young career and it challenged what I thought I “understood” about human interactions with animals.  Keep in mind, I was known for being an animal whisperer of sorts in my youth (see below) and truly believed that my special calm and confident nature could be detected by animals, and that they would accept my presence more readily than those who didn’t have my nature.  That FernGully perspective is wrong and egocentric.  There are few scenarios where our presence isn’t horribly stressful and disruptive to wild animals.   

Squirrel demonstrating a cost/benefit analysis = the benefit of free food is higher than the stress my tie-dyed presence is causing.

Large predators are no exception.  They are just as vulnerable to our stress as cormorants and just as unlikely to express it externally, because the cost of those behaviors is expensive.  Predators have severe energetic constraints and are constantly calculating whether their actions are worth sacrificing energy for, this is a cost/benefit analysis.  We do similar analyses all the time.  For example, I have a Trader Joe’s that is ~30 minutes from my home.  The food there is delicious and less expensive than my local grocery store.  However, I don’t go to The Joe every time I am hungry.  Even though I would save money on discount blue cheese dip there, I would spend more money in fuel for my car – meaning the entire trip would cost me more in the long run.  The costs of this behavior is too high and not worth it.

White sharks are especially discerning since they can burn a lot of energy quickly and are unlikely to encounter large meals in the open ocean to refuel.  So they make conservative decisions that prioritize maintaining energy stores (especially during gestation when a large portion of their energy budget is developing shark embryos).  In the recent case of large white sharks scavenging from a sperm whale in Hawaii, there were several divers in the water creating close interactions with the sharks for social media purposes.  Controversy ensued and the idea that the white sharks must have “enjoyed” these interactions otherwise they would have swam away or bit the divers has been presented.  But it is not supported.  First, white sharks full of whale blubber are experiencing some pretty hardcore torpor.  Also, blubber is very positivity buoyant, meaning a stomach full of blubber is essentially the same as if we ate a ton of foam and then tried to swim about.  White sharks at whale carcasses are typically slow-moving with low aggression, even towards each other.  It’s not that whale blubber makes them “happy,” it’s that being aggressive and swimming fast when there are going to be many other white sharks around AND you’re going to have a stomach full of floaty blubber is energetically expensive and the costs of these behaviors are too high.

Figure 4 from Fallows, C., Gallagher, A. J., & Hammerschlag, N. (2013). White sharks (Carcharodon carcharias) scavenging on whales and its potential role in further shaping the ecology of an apex predator. PLoS One8(4), e60797.

Does that mean diving with full-bellied white sharks is safe?  Absolutely not – for them or for you.  It doesn’t matter how well you think you “know” a predator – species or individual – they are still dangerous.  We all know the list of fatal tragedies that start off with well-known humans believing that they have enough experience to take big risks, and each of those fatalities ends with the animal suffering, too.  For the sharks, disrupting a rare feeding event has long-term implications.  The stress caused – whether they exhibit that stress externally or not – is burning their limited energy, forcing them to recalculate their future behaviours until (if?) they encounter the next windfall.  Also – although currently undocumented – it’s a common thought amongst shark researchers that mating could occur at large feeding events like whale carcasses since it’s provides male sharks an opportunity to take advantage of the large female’s torpor to attempt mating approaches (I personally believe the same is true at seal colonies).  Boats and divers disrupt these behaviours.

I don’t bite every person that causes me stress.  I don’t full-sprint away from every situation that causes me stress.  That doesn’t mean that I am not experiencing stress that impacts my behavior and health.  The same is true for every one of these close animal interactions created by humans.  It’s alarming to me when those humans say that they are somehow especially qualified, and that their experience alone creates these “safe” encounters.  It’s not.  You’re benefiting from the cost a large predator doesn’t want to incur by demonstrating its stress to you – but as we’ve unfortunately seen several times, when the scales are finally tipped, unnecessary tragedies do occur.

Florida releases draft land-based shark fishing regulations

After months of expert and public consultation, the Florida Fish and Wildlife Conservation Commission has announced the draft text of new regulations that will govern land-based shark fishing. It’s mostly very good news that directly addresses most of our concerns! 

A review of the problem
Land-based anglers in Florida (those who fish from beaches, docks, and piers) catch large numbers of threatened, protected species, handling them in needlessly cruel ways that likely result in mortality or permanent injury. Anglers are aware that what they’re doing causes harm to certain species and violates some existing regulations. Hammerhead sharks in particular are extremely physiologically vulnerable and need to be released much faster than they are currently being released or else they will very likely die. 

(Learn more: see my paper on this subject, my blog post summarizing that paper, an open letter calling for action, an op-ed I wrote about thisa review of the existing rules and how they’re regularly violated, and a years-old blog post describing one problematic incident with land-based shark fishing)

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Fun Science FRIEDay – The Break-up

Our lives are a blip in the space time continuum. As a result, it can seem that the Earth is relatively static, with many of the large scale dynamic changes that shape our sphere largely unnoticeable to us occurring on geological time-scales. One such change is the movement of landmasses on earth, better known as plate tectonics.

Earth’s landmasses are not static but in constant flux. The Earth’s lithosphere (formed by the crust and the upper part of the mantle) is broken up into a number of tectonic plates that move relative to each other at varying speeds, “gliding” over a viscous asthenosphere. There is still ongoing debate about what force or forces causes this movement, but whatever the forces are they can also cause the plates to rupture, forming rifts, and potential leading to the development of new plate boundaries. When this happens landmasses break-up and new continents forms; this is currently happening in the East African Rift in southwestern Kenya.

View of East African Rift in Kenya from space (Photo credit: Google Earth. Data SIO, NOAA, US Navy, NGA, GEBCO).

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A precautionary approach to health and safety while using awesome, awesome laser cutters in the home.

Holy Mola, Laser Cutters! If you follow me on Instagram, you’ve probably seem some pretty cool projects coming out of my freshly arrived Glowforge laser cutter.

But laser cutters are not all sunshine and cool, wooden hinges. Laser cutters were, until very recently, the domain of industrial fabrication shops with extensive safety systems. As a new generation of low(er) cost, hobby and household cutters enter the market, we need to step back an think critically about the potential health and safety impacts of these incredible machines.

Like I did with 3D printers a few years back, I’m taking a deep dive into the hazards of laser cutters in the home and how to avoid them.

First, the issues of least concern (not because they aren’t bad, just that they’re far less likely to occur).

Fire. Lots of materials can catch fire, including, to no one’s surprise, wood. A fire safety plan will go a long way, but you can avoid ruining your laser cutter by being aware of what materials frequently catch fire. ABS, HDPE, polystyrene and polypropylene, and anything with poor thermal properties is going to ignite rather than cut cleanly. And then you’re going to have a bad day.

Beam escape. If your machine is not well taken care of and well shielded, there’s a small chance the wrong materials or loose connections can result in a beam escape, which can injure the user, bystanders, pets, or anything else that gets in the laser’s path. Most hobby grade lasers have good safety features to prevent this (although cheap knock-off machines are starting to hit the markets that may not be up to par), but monitoring you equipment and keeping it properly maintained will go a long way to avoiding this.

But those aren’t the biggest concerns. Th biggest concern with laser cutters is the byproduct that happens every time you cut, no mater what. That’s right, I’m talking about:

Fumes! 

This is the big one and the issue that I’m most concerned about. Laser cutters haven’t really left industrial settings until now, so we don’t have very good data on chronic exposures of laser cutting fumes, especially on young children and pregnant people. What we do know is that the fumes produced by laser cutter depend heavily on the materials you choose to cut.

All materials will produce fumes when cut, which is why it’s essential that your set-up is well-ventilated. Most hobby cutters have a vent port that you can connect to a dryer vent or to the outside. I actually don’t recommend using a dryer vent. In all the rental houses I’ve lived in, not one has ever had the dryer properly vented, and hooking up to your dryer port might mean that you’re just venting into the crawlspace or the wall, rather than out of you house. Go for the window. There’s no hard and fast rule for how much ventilation you need, other than as much as possible. For 3D printers we recommended that your ventilation system moves 3 times as much air as the volume of the room per hour. For laser cutters, it should probably be more.

Everything you cut is going to release volatile organic compounds (VOCs), which is why ventilation is essential. For things like hardwoods and paper products, the VOCs released are comparable to a woodburning stove, frying too much bacon, or sitting around a campfire (though sitting around a campfire will give you a much higher dose). Prolonged exposure can cause respiratory problems and asthma. More complex materials like plywoods and plastics can have some pretty nasty compounds, so you want to make absolutely sure you know what’s going into your laser cutter, be aware of what materials should never, ever go into you household cutter, and always ventilate, ventilate, ventilate.

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Imaginary islands, lobster pain, porgs and puffins: Thursday Afternoon Dredging, January 25th, 2018

Cuttings (short and sweet): 

Spoils (long reads and deep dives):

Please add your own cuttings and spoils in the comments!

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