Trash to treasure! Strandings on the tideline

DSC_0077 low resI think it’s fair to say that finding a large dead fish washed up on a lovely walk across the beach is not everyone’s idea of a great day out… however whether fresh and slightly sad or degraded and frankly disgusting, a dead sunfish slowly rotting away has the unbelievable ability to enhance my day. As a conservation biologist, I have never killed a sunfish for research purposes; however there is a treasure trove of information that can be collected from examining a dead fish, from deep tissue samples for isotopic analysis of diet, to extracting vertebrae for age analysis, there is so much still to learn about these fascinating fish! Alongside cutting edge analyses of tissues, examining a carcass also provides an unparalleled opportunity to learn about fish morphology from old fashioned dissection and exploration.

Throughout my PhD I have been seeking to 20140922_100521collect as many stranded sunfish as possible but these are relatively few and far between. I was provided with one large individual from Lough Foyle, Northern Ireland that was kindly collected by the Lough’s Agency in 2015 (so-called ‘Murray the mola’) and last year we spotted photos on Twitter of a small specimen that had washed up in Kimmeridge Bay in Dorset, England. Luckily ‘Kim’ was found by marine biologist Julie Hatcher who kindly held on to it until I could arrange a lift to transport the fish to my parents’ house, where it lived in their home freezer for a few days until I brought it back to Belfast boxed up as my hold luggage (bit of a weird Doreset stranding.jpgone to explain at Customs!) Following these collections I needed to organise a formal dissection, an event which transformed into one of the highlights of my PhD to date. Although I had tried my hand at dissections at school and during my undergrad degree, I had never been particularly confident in identifying one squishy blood-stained tissue from another squishy stained tissue and I struggled to get past the ick-factor, which as a wanna-be biologist left me feeling disheartened (not to mention a bit queasy!) Luckily, with a few tips and tricks on dealing with appalling smells (vapour rub under the nose works a treat) and an ever-increasing enthusiasm to learn more, I’ve been waiting for a chance to try again.

Photos: Top left, Murray the Mola; Top right Murray wrapped up in the car to Belfast; Middle left Julie Hatcher and Kim sunfish; Central row Kim’s journal from freezer to boxing to Belfast!

In Italy last year I posted a short blog about a small dead sunfish caught accidentally as bycatch in the local fishery which I carried home on the train in a shopping bag and dissected over the bidet in my rented apartment. Thanks to its strange dinner-plate shape, the ocean sunfish’s internal organs are beautifully laid out and navigation of differing organs is made simple by vivid colours which I had never noticed in undergrad IMG_20160621_124245.jpgclasses when working on greyish farmed trout. Beneath the thick skin and muscle layers, the sunfish gall bladder is bright green, the liver a faded mustardy yellow and the heart of course a deep dark red.

After this brief exploration of sunfish anatomy, I was really looking forward to learning more about the intricacies of dissections with our larger specimen in Belfast. This experience was further augmented by the opportunity to work alongside Prof John Davenport (something of a legend in the anatomy world).  The last full dissection of an ocean sunfish was published in the 1920’s so it was fascinating to pull together all the notes we could find on their internal structure (which turned out to provide a rather limited reference library) and get stuck in!

We spent 4 days slowly working over Murray Mola from nose tip to tail exploring every Snapshot dissection.pngtiny detail that struck us as interesting (for more info watch this space)! The whole dissection process was fascinating and incredibly valuable, from learning about internal structuring to collecting further samples for my PhD research and we all were struck with how much could be gained from a single specimen.

Photos: Above left, Whistling on the train *no sunfish dripping here…; Above right, sunfish dissection in 33 degree heat in the apartment bathroom.

It is always a sad sight when a stranding occurs, but thanks to the wonderful people who patrol the beaches and report their sightings, we can make the most of every opportunity to learn more about these incredible fish. If you spot a stranded sunfish we would love to hear about it! Please contact me using the comments section below or email me at: or tweet @sunfishresearch

So long and thanks for all the fish!


It’s that time of year again, spring is in the air (mostly!) and thoughts turn to summer holidays relaxing on the beach, swimming in the sea, snorkelling over colourful corals and silvery fishes. But what is the future for these seemingly idyllic ecosystems? Current research suggests that coral reef ecosystems globally are under mounting pressure, from warming seas, acidification, over fishing, tourist damage etc., however until this week I was unaware of the potentially wide ranging impacts of the tropical fish trade. As someone who has kept fish as pets and occasionally visits aquariums, I wanted to know more about how fish are sourced for aquaria displays.

finding nemo.jpg

A recent article from National Geographic states that up to 98% of marine ornamental fish cannot be bred in captivity on a commercial scale; therefore they must be collected from the wild, namely from Southeast Asia. According to a report from NOAA in 2008, up to 90% of the 11 million marine aquarium fish imported to the USA are caught illegally using cyanide. Although fishing using cyanide has been banned across the Philippines, Sri Lanka and Indonesia, there is little enforcement and with huge sums at stake, more and more fishermen are turning from fishing for food to supplying the aquarium trade (worth up to $200 million p.a. according to the WWF).


When cyanide tablets are ground down, they can be mixed with water and using squeezy bottles, used to flush out stunned fish from hiding places in the reef. Cyanide impairs movement and breathing in fish and with such an imprecise method of delivery, many simply die. It has been estimated that for each fish collected, a square yard of coral is killed or bleached (which of course has further knock on impacts across the reef ecosystem). It appears that both the fishermen and middle men involved in this trade are very quick to pass on their catch, as there is a high risk of fish death, even some time after collection and then of course the risk is passed onto the unsuspecting aquarium owners who will need to replace their collection if a fish dies. But what can be done to break this cycle and ensure that fish are ethically supplied from sustainable sources?

Bags of fish.

New laws are currently being drafted globally, with new legislation being debated and huge petitions aiming to make cyanide testing and certification of imported fish mandatory. However, this does not reduce pressures on tropical fishes still being collected from the wild in huge numbers, and many are now calling for only captive bred fish to be sold and traded. It is perhaps ironic that after the release of Disney’s film Finding Nemo (in which a wild fish is taken off the reef for a private aquarium and the tank fish fight for freedom in the open ocean), demand for clownfish and tangs shot up by 40% almost overnight.

Although many clownfish species can be bred in captivity, royal tangs are now being over collected and are endangered in the wild. A new app called Tank Watch (developed by the Humane Society of the United States) aims to help people trace reef-friendly species and public awareness campaigns are aiming to educate people (like me) by highlighting the potential back story of each aquarium fish.


Of course on the flip side, the aquarium trade has benefitted some rare species, such as the red-tailed black shark which is critically endangered and possibly extinct in the wild, but thanks to the the interest generated by aquarists,  dedicated breeding programs have been set up and a steady captive population now can help preserve this species.

It’s a contentious issue, with opinions running strongly on both sides, including the “Hands off my hobby” campaign of the Ornamental Aquatic Association who aim to protect the “pleasure [gained from fish keeping] as well as [the] social, economic and
health benefits” of the fish trade to the UK. On the opposing side, marine campaign groups such as Sea imagesShepherd have launched their “Operation Reef Defence” to end the wild caught marine fish trade.

Public support is now building for a European wide investigation into the exotic pet trade, and perhaps the end goal should be to ensure ethical standards and protection of reef ecosystems are upheld so that at the end of the day, everyone can sit back and enjoy the fish.

If you fancy more fishy facts (or if you have found a sunfish washed up) please contact me using the comments section below or follow me on Twitter or Instagram @SunfishResearch  🙂

Myth buster’s blog part 2: Farewell fake news!

Hello and welcome to Part 2 of the special edition Myth Buster’s Blog!! Following the fishy facts touted by sunfish-loathing Scout Burns that went viral last week, I have been exploring the incredible ecology of the ocean sunfish and answering a lot of fake news claims! So buckle up and get ready for a whistle-stop tour of fascinating (and scientifically verified!) fish facts.

My favourite issue that Scout has with sunfish is that despite being “so huge” they are not even “decent predators” …unless you are a prey item of course! The key biological definition of a predator is ‘an animal that naturally preys on others’ and so sunfish are actually classed as oceanic predators!


With jaws not-so-dangerous to people, the sunfish (or Mola) is a voracious predator of gelatinous prey!

 If we consider a “decent predator” as one which is harmful to humans, then as Scout mentioned, sunfish can be dangerous due to their incredible size and are alleged to have caused a death already by breaching and hitting a person. But as a biologist, this doesn’t seem like the best method for classifying predators…(although it should qualify as entry to the Darwin Awards!)

Back to sunfish prey items, (an area quite a few researchers have been working on over the last 5-10 years,) Scout states “They mostly only eat jellyfish because [it has] a possibility of drifting into their mouths I guess. Everything they do eat has almost zero nutritional value and because it’s so stupidly fucking big, it has to eat a ton of the almost no nutritional value stuff to stay alive. Dumb.” Again, this statement needs a bit of work to reach the underlying truth… Yes sunfish mostly eat jellies, but for smaller sunfish (<1 m), up to 40% of their diet is actually made up of seafloor creatures including crustaceans, molluscs and even some fish species. I even wrote a blog post about this 3 years back…

sunfish food

So many choices….

To find jelly prey in the open ocean, not just jellyfish medusae but also other gelatinous creatures such as siphonophores, ctenophores and pyrosomes (see photos!), is a tough job. Sunfish constantly patrol the world’s oceans searching for prey, travelling long distances both horizontally and vertically to find their food. When they locate prey items, such as a jellyfish, they know to only eat the most energetically nutritious parts, the gonads and oral arms (yum!) before leaving the rest as not worth bothering digesting. It’s an incredible strategy that not many creatures are physically able to exploit and something that we are still trying to understand and explain.

Sunfish prey items clockwise from top left: Ctenophore – (Bolinopsis infundibulum), Siphonophore (Marrus orthocanna) and Pyrosome (unknown species)

Photo credit,,

Scout then moves on from thinking of sunfish prey, to thinking of sunfish as prey: “They do sometimes get eaten though. But hardly. No animal truly uses them as a food source.” Again, this is a little misguided. Although larger sunfish are less predated on (but have still been found inside large sharks, sealions, orca etc.) the sunfish start out life in the plankton as tiny eggs less than 1 mm across. This puts them on the menu for almost every creature in the sea! As they grow, the number of predators able to cope with such a large item decreases, but they are still removed from the world’s oceans in their hundreds of thousands by… you’ve guessed it: us! There are huge markets for ocean sunfish meat across the Far East (Taiwan and Japan in particular) and they are also captured as unwanted bycatch by fisheries across the world. It is these enormous catch figures that have led to the ocean sunfish being classified as Vulnerable to extinction by the IUCN Red List.

Fisheries capture of ocean sunfish and a dish made of sunfish

(Photo credit; Lukas Kubicek and

Scout reckons their survival strategy is dependent on the sunfishes extreme fecundity, “it would be statistically improbable, dare I say impossible that there wouldn’t be at least one… left surviving at the end of the day”. The sunfishes incredible fecundity has been estimated from one study that suggested a single female could contain up to 300 million eggs, (although it is highly unlikely that a sunfish would release all their eggs at once!) This number is brandished a lot in ocean sunfish ecology, but we need to remember this figure was estimated from one fish; it does not represent the average number of eggs per sunfish and has not been examined further since the original study in 1921…

The statistically probability of larvae survival is harder to predict… in cases of extreme fecundity (known as being an r-strategist) an animal must produce lots and lots of offspring because the overall odds of survival are minuscule. We don’t currently know how many sunfish there are in the seas, but it appears that not many of these offspring survive otherwise evolutionary speaking, it would be an unnecessary waste of resources and not selected for.

r stratagist.png

A simple outline of species reproductive strategies:

  1. “K strategists” which have fewer offspring with higher energy input and high parental care which are more likely to survive (e.g. polar bear)
  2. “r strategists” which have high abundance of offspring, with low energy input and little to no parental care which have a poor chance of survival (e.g. ocean sunfish)

Of course this rant does not, in my opinion constitute as “proof that God has abandoned us.” But unfortunately Scout feels so strongly to “hate the f*** out of this complete failure of evolution… if I ever see one, I will throw rocks at it.” As much I as love to introduce people to the incredible species I work on, considering that we currently believe these fish are Vulnerable to extinction and seem to have an important role in ecosystem functioning, (and animal cruelty is frowned upon), perhaps it’s best that these two never meet.

If however, anyone ever has any questions on ocean sunfish or wants to know more details about their fascinating ecology please head to my twitter page @SunfishResearch or visit my blog


Something Sounds Fishy! Myth Buster’s Blog (1 of 2)

break the internet.png

Incredibly it seems the ocean sunfish has gone viral yet again! I know, I was surprised too! Firstly Boston Man broke the internet with his ideas of catching a ‘baby whale’ (*spoiler, it’s a sunfish!) and now an incredible rant about the “biggest joke played on earth”, again with sunfish as the butt (or should that be swimming head) of the joke! I love a good rant (esp. David Mitchell when he goes off on one), but in the dark days of fake news, there are a few little problems with Scout Burns’ epic tale of “wasted space” that I feel we should explore.


Fishy News Stories…. Time for #FridayFacts!!

Scout has made some pretty big claims about sunfish, the scientists who study them and even the process of evolution itself so I feel it’s time someone stood up for the funny-looking fish and for science itself, so in response today we have a special #FridayFacts edition: The Myth Buster’s Blog!

At the beginning of this viral rant, we are told that sunfish are just “big, dumb idiot[s]” of “the biggest joke played on earth” made when “God must have accidentally dropped [one] while washing dishes one day and shrugged his shoulders” because they have “no purpose… every foot… wasted space”. Of course we cannot agree with this, the ocean sunfish is the brand new kid on the block when we come to looking at species evolutionary speaking! Whereas the fishes as a group first emerged around 500 million years ago, the ocean sunfishes represent cutting edge evolutionary design, having evolved only around 50 million years ago!



Dishes?! More like cutting-edge design

The ocean sunfish showcases a fantastic body honed by selective processes over millions of years, perfectly adapted to a life travelling the world’s oceans. As to their purpose on this planet, this is a bigger question to answer… the meaning of life has been hotly debated for centuries from ancient philosophers to Monty Python (of course the real answer is 42!). But roughly speaking, their “purpose” is the same as the rest of all lifeforms on earth… simply to exist and pass on genes: to feed, grow, breathe, reproduce and die.

The meaning of life and the sunfish life cycle (adult produces offspring as eggs, through larval stages, growing from juvenile to mature adult and the whole cycle starts afresh!)

Of course, having an interest in biology, we want to know a few more details than that! Which is why scientists (myself included) are trying to unravel the complex ecology of the sunfish a little further… but when it comes to scientific understanding, Scout suggests “scientists even debate how [sunfish] move. They have little control… some say they must just push water out of their mouths for direction…They could use their back fin, except… it doesn’t f****** grow. It just continually folds in on itself.”

Now as funny as the idea is of a giant sunfish blowing water to presumably jet backwards (!?!), I am sorry to report that this simply isn’t true. We know how they move and in quite a lot of detail. They use their dorsal and anal fins like a pair of wings to soar through the oceans, undertaking long distance journeys of up to 48km a day! Their funny little caudal fin (known as the clavus) grows of course, and has a vital function (otherwise evolutionarily it would have most likely have been lost!), and is used like a ship’s rudder to steer the fish as it swims.


Similar structures; ships rudder and sunfish clavus

Scout correctly mentioned that sunfish don’t have swim bladders; however it is not true that “that every fish has [one] to make sure it doesn’t just sink to bottom of the ocean… [and sunfish] can barely move to begin with”. Lots of fish do not have swim bladders, for example sharks, as there are other evolutionary designs that can provide lift without the issues of containing air internally (such as problems with rapid descent and ascent). Most fish without swim bladders, including sunfish, have large deposits of fatty lipids in their livers that provide buoyancy = no swim bladder, no problem!


Some of the sunfish’s fellow fishes without swim bladders (left to right: manta ray, great white shark, basking shark, white marlin)

Aside from preventing sinking, Scout also mentions that sunfish seem to “get stuck on top of the water… because without the whole swim bladder thing… the ocean pushes over the [fish]”. This idea again presents a great image, but unfortunately is untrue. The sunfish does not need a swim bladder to remain upright (it’s not a life jacket); they are perfectly capable of swimming upright both at the surface and at depth. Sunfish are often noted “basking” at the surface where they lie on their sides which enables them to increase the rapidity of their heat exchange, to communicate with birds for parasite removal and perhaps simply just to rest, before diving back into the depths (up to 844m deep!)

sunfish depth.png

Seeking the sun in deep, dark places! Ocean sunfish photos at depth

So that’s all we have time for in this Myth Buster’s Blog edition but I will be posting part 2 next Friday to question the remaining “fishy” facts in the “sunfish are useless animals” rant and of course to provide some illuminating answers! *Spoiler alert, sunfish are awesome super-predators!

If you just can’t wait another week for more sunfish news, please check out my twitter @SunfishResearch or please feel free to ask a question using the comments below 🙂


Getting crafty for Science! From paddling pools to pleather harnesses, all in a day’s work!

I am often asked where I find equipment for my research, (obviously sunfish harnesses can be tricky to buy off the peg)… and so this blog is all about sourcing strange bits of kit! Please dive in and feel free to laugh a lot at the awkward places I end up, all in the name of science!

A common strategy for many scientists is to make your own/adapt/invent things to fit your fieldwork and although this may seem a bit Blue Peter “here’s a floating, lightweight holding net I made earlier”, it saves a lot of money and time in the long run!

A “how to” make a floating net (including demo ‘fish’ capture in last photo…)

So to start the blog for 2017, here is the official Weird Kit List! The top 3 things I have bought or made in the name of field work (so far…)

   At number 3: The beef jerky maker/high tech stable isotope dryer!


The state-of-the-art isotope lab in action (in my b&b room *phew!)

At number 2: The suspicious hand pump/chlorophyll extraction device!



The hand pump in action on the beach filtering liters of seawater in double quick time!

And at No. 1: The pleather lovers’ dream/sunfish-harness-making material!


Customised sunfish belts for all!

So as you can see, it’s well worth being a bit inventive (and having a sense of humor) when working in the biological sciences!!

Here’s to another year of invention & adventure and wishing you all a wonderful 2017!

As always if you see a dead sunfish which we could take samples from or just fancy a chat about fish/PhD life/getting crafty for science please get in touch! 🙂


Twitter: @SunfishResearch

Instagram: @SunfishResearch

The unbelievable truth: 7 surprising sunfish facts!

After writing this blog post about the unusual behaviours of ocean sunfish, I was searching for illustration inspiration… and here we are!


Over the last two years I have seen hundreds of sunfish and these close encounters have given me plenty of opportunity to note a few things about their unusual behaviour!

 So here are the seven strangest things I have learned about sunfish so far:

 1.      Sunfish are noisy! It may sound strange, but yes fish really can make noises (a useful communication tool in the marine environment as sound travels more easily through water than air). Our sunfish grumble and grunt (a lot!) in a disgruntled fashion, especially when we weigh them, (but then no-one likes having their weight read out loud I suppose?)

sunfish close up

Puff your cheeks out! (pre-grunt)

2.      They can throw mucus a distance of several feet! I’m pretty sure this is an unintended consequence of being very mucus-y fish with powerful flapping fins, so if anyone else is planning on working with them, beware of flying gunk -it gets everywhere: clothes/arms/ears/hair etc. eugh.

3.      Sunfish can projectile poop. Yes you heard me, I was not prepared for that either. We were trying to collect some faecal samples for gut content analysis and things may have got out of hand (more literally than I like to remember!) Also hysterically funny! Only slight issue is that sunfish poo is bright orange and smells appalling. (I mean no one expects faecal samples to smell good, but this was unbelievable.)

sunfish poo.png

Sunfish poo… to be avoided at all costs!

4.      Although they look smooth, beneath the mucus layer, the skin of sunfish is very rough to the touch so if a flapping fin catches your arm, it’s exfoliating to say the least, like being towelled off with sanding paper.

5.      Sunfish blink. They have a strong white muscle around the eye socket that they can use to wipe the eye or pull it back in if feeling threatened. Bit disconcerting when they wink at you… then shower you with slime/poo/seawater. Nice trick.

sunfish eye.png

Photo on left shows the eye pulled in, protected from the measuring tape and then on the right, the fish peeks out again to see what we are doing… sneakily does it!

6.      They are strangely curious fish, frequently swimming right up to the camera or hovering just under the boat looking up at us. The fishermen sometime use brooms to try push them away and prevent tangling!

Curiouser and curiouser…

7.      Sunfish have a sense of humour. Okay, maybe I made this one up, but I watched Lawrence wrestle a particularly large one into the weighing tarpaulin and get slapped around the face for his trouble by a large fin… slapped by a wet fish!! Needless to say I think the fish won that battle.


Oh my what big fins you have?! All the better to slap you with!

If anyone has seen a stranded sunfish or has more sunfish pub facts, please use the comments section to get in touch or email me:, or for further photos and project updates follow me on Twitter: @sunfishresearch or on Instagram: SunfishResearch

I guess we’re not in Kansas (City) anymore… The Monterey Bay Aquarium!!

Part 2 of the great American road trip! I have been really lucky throughout this PhD to talk with amazing sunfish researchers from all over the world, although to date, most of these meetings have been on skype!

Since the AFS conference had brought me all the way to Kansas City, it seemed silly to go home without trying to catch a few sunfish people in the States… so it was just a short hop over to California where I had been able to arrange meetings with none other than Michael Howard (senior sunfish aquarist at Monterey Bay Aquarium) and Dr Tierney Thys (National Geographic explorer)!!

California… here we come!

Along with every marine biologist in existence, I have always dreamt of taking a trip to Monterey for the world famous research labs, aquarium and wildlife. Michael’s ground-breaking work at the aquarium; keeping the seemingly impossible sunfish on public display, sharing hard-earned knowledge on handling and sampling protocols, and satellite tagging sunfish on release is world-renown.

In Monterey I was able to join him for a week ‘behind the scenes at the aquarium’, which seems the most amazingly diverse job! As part of the open ocean team I spent my week searching for sunfish at sea, observing tuna tank transfers, learning about growing jellies for display and even hand-feeding a sunfish (a definite career highlight!) It was an incredible experience to see the dedicated research that goes into caring for such an amazing array of creatures and constantly improving animal welfare standards. Just from walking around the aquarium, it was clear how this approach provides an inspirational experience for all visitors, showcasing the beauty of the natural world and highlighting conservation issues.

Monterey Bay Aquarium

We were hoping to use some of the techniques from my fieldwork (mucus sampling, deploying accelerometer harness systems etc.), on captive sunfish in Monterey, to increase our dataset and to validate all methods in controlled environments… however the fickle finger of fate intervened and unfortunately there was only one little sunfish left in the tanks when I arrived.

As this fish was the “heir to the throne” as Michael put it, getting ready to go on display and inspire thousands of people to care for the marine environment, there was no chance I would be able to play with it! So we went out on the bay every other day searching for wild fish. Although we observed plenty of wildlife, (humpback whales, Risso’s dolphins, seals, otters, sealions and one whopper of a sunfish, too big to collect ~100kg!), collectable sunfish remained elusive. Even the best laid plans…

Stealing the sunfish spotlight…

However, despite the lack of sunfish (which is something I really need get used to!) I gained an incredible amount from this experience, particularly relating to handling and dietary requirements which is vital to my research. During the week I also gave a seminar on our work on ocean sunfish at Belfast to a packed room of fish enthusiasts (researchers, aquarists and volunteers) and the feedback was wonderful!

Sunfish seminar

Alongside my incredible week at the aquarium, I was able to finally meet Tierney in person after working with her on a couple of sunfish papers over the last two years! Over dinner with her lovely family we spoke about sunfish for hours *apologies again to Bret & the kids* and examined her treasure trove of sunfish merchandise from badges, bags and bathroom flannels, to chopsticks, toys and charms. (I clearly am very behind on my sunfish collection!)

It was an incredible evening, to meet someone whose work has inspired so many in this field (including my own career). If anyone reading this blog is unfamiliar with Tierney’s work, I would highly recommend starting with her amazing (and super funny) TED talk on sunfish.

Image result for tierney thys

Click on the link to Tierney’s sunfish talk above!

One of best parts of undertaking a PhD are the incredible opportunities to meet people who have the most amazing careers changing the world for the better. This trip has been truly inspirational and I am so very grateful to my funding bodies and grant providers for making this possible.

Marine inspiration

If anyone has any questions or comments about marine biology, PhD life or sunfish please get in touch!

-Comments section below

-Twitter: @sunfishresearch

-Instagram: SunfishResearch