HON­DURAS

STU­ART PHILPOTT spends some time with the Whale­shark and Oceanic Re­search Cen­tre on the is­land of Utila

Sport Diver - - Contents - Photographs by STU­ART PHILPOTT

Stu­art Philpott spends some time div­ing with a whale­shark re­search cen­tre on the is­land of Utila.

Surely life couldn’t get much bet­ter than liv­ing on a Caribbean is­land and work­ing at a whale­shark re­search cen­tre. On my re­cent trip to Utila, si­t­u­ated off the Hon­duran coast, I vis­ited the WSORC ( Whale­shark and Oceanic Re­search Cen­tre) based at the Utila Dive Lodge. Bri­tish born Kon­rad Madej had been man­ag­ing the cen­tre since Septem­ber 2015, and from what I could see, he was hav­ing a whale of a time. The fa­cil­ity at­tracted stu­dents and vol­un­teers from all over the world. Usu­ally they stayed for pe­ri­ods of be­tween one to six months to write papers and carry out re­search work which could be any­thing from data col­la­tion and li­on­fish dis­sec­tions to whale­shark tag­ging.

Utila is a hotspot for year-round whale­shark (Rhin­codon ty­pus) sight­ings so where bet­ter to set up a ded­i­cated re­search cen­tre. The peak sea­son is be­tween April, May and June. Us­ing air sup­port will al­most guar­an­tee sight­ings. Kon­rad told me that ear­lier in the year a French film crew had hired an old Bell Huey chop­per for a two-day shoot and had got plenty of close-up shark footage for their doc­u­men­tary. Un­for­tu­nately my bud­get was not on such a grand scale so I had to make do with a dive boat sup­plied by Utila Lodge and around twenty pairs of eyes vig­i­lantly scan­ning the hori­zon. I had also ar­rived a month out­side of the main sea­son so my chances weren’t look­ing great.

The WSORC (www.wsorc.org) has been mon­i­tor­ing whale­sharks since the late 1990s. Kon­rad said: “When we are search­ing for whale­sharks we nor­mally look for con­gre­ga­tions of sea birds div­ing into the wa­ter.” This usu­ally denotes a ‘boil’ where shoals of sil­ver­sides or an­chovies have been forced to the sur­face by preda­tory tuna. The whale­sharks pick up the acous­tic noise from the feed­ing tuna and home in on the ac­tion.

Stu­dents are en­cour­aged to bring their own un­der­wa­ter cam­eras so that they can photo ID the whale­sharks. Kon­rad said: “By the fifth gill slit at the base of the pec­toral fin on the left hand side there is a unique pat­tern of 12-15 spots.” They also record any scar­ring, sex, size, num­ber of re­moras at­tached, site lo­ca­tion, how many peo­ple are in the wa­ter with the shark, how boats are in­ter­act­ing and whether they are break­ing any reg­u­la­tions. All this in­for­ma­tion is added to the WSORC database.

Re­cently Kon­rad had been con­duct­ing pi­o­neer­ing re­search into the mi­gra­tory routes of whale­sharks. To help with his stud­ies a com­pany called Liq­uid Ro­bot­ics (www.liq­uid-ro­bot­ics.com) had do­nated two USD$400,000 state-of-the-art SHARC wave glid­ers. The wave glid­ers are ba­si­cally drones that can track whale­sharks tagged with a trans­mit­ter. This in­for­ma­tion is sent back to Kon­rad’s com­puter via a GPS link.

We made a slight de­tour dur­ing our whale­shark ex­pe­di­tion so I could get a closer look at the in­no­va­tive wave glider. From the sur­face the unit looks just like a 3m x 80cm surf­board con­structed from ti­ta­nium and fi­bre­glass to with­stand harsh sea con­di­tions. The wave glid­ers are usu­ally painted yel­low for com­mer­cial projects or black if used by the mil­i­tary. I grabbed my scuba gear so I could check out what was hap­pen­ing be­low the sur­face. At a depth of ap­prox­i­mately 4m there is a series of me­chan­i­cal pad­dles all linked to­gether. As the surf­board rides over the waves the en­ergy is trans­ferred to the pad­dles, thus creating for­ward propul­sion. With the ad­di­tion of two so­lar pan­els there is enough power to re-charge the GPS trans­mit­ter/re­ceiver bat­ter­ies mak­ing the unit to­tally main­te­nance-free for sev­eral years. There is also a col­li­sion de­tec­tion sys­tem. I was sur­prised how fast the wave glider was ac­tu­ally trav­el­ling. In fact, I could barely keep up! Kon­rad said the wave glider has a top speed of around three knots. Way be­low the pad­dles (at about 10m) hangs the tor­pedo-shaped acous­tic sen­sor which picks up the sig­nals from the whale­shark tag trans­mit­ters. This was sur­rounded by a shoal of ju­ve­nile jacks. Some­times even tur­tles swim along­side.

Kon­rad said: “The hard­est part of the job is at­tach­ing the trans­mit­ter tags to the whale­sharks.” The skin on the larger males is so thick that a barb fired from a spear gun just bounces off. Kon­rad had ex­per­i­mented with a va­ri­ety of dif­fer­ent spear­guns and even­tu­ally set­tled on us­ing a pow­er­ful dou­ble band ver­sion. He aims for the base of the dor­sal fin. He showed me some video footage of the pro­ce­dure and the shark doesn’t even feel the sharp look­ing barb. In 2016 the WSROC suc­cess­fully tagged three sharks, the largest be­ing a 12-me­tre-long male and the small­est a 4-me­tre male. The acous­tic tags cost around $1,000 each. Kon­rad said he only had enough funds to buy five but he would ideally like to have at least twenty tags and five wave glid­ers in the field. Any pri­vate dona­tions are more than wel­come!

Two weeks be­fore I ar­rived there had been mul­ti­ple whale­sharks sight­ings. But same old story, when I ap­peared, there were none to be seen. We spent the whole day search­ing for some bird ac­tiv­ity. There were a few in­di­vid­u­als fly­ing about but this didn’t lead to any­thing fruit­ful. As a con­so­la­tion Kon­rad took me to Nep­tune’s bar where I ac­tu­ally caught sight of my first whale­shark - a cock­tail made from blue cu­ra­cao and white rum, with white spots made from tapi­oca. The bar staff wouldn’t di­vulge the ex­act in­gre­di­ents - ap­par­ently it’s a trade secret.

“The in­no­va­tive wave glider looks just like a 3m x 80cm surf­board con­structed from ti­ta­nium and fi­bre­glass to with­stand harsh sea con­di­tions”

Caribbean li­on­fish (Pterois voli­tans) are an invasive species, and have no nat­u­ral preda­tors. There seems to be a num­ber of dif­fer­ent sto­ries as to how they ended up in the Caribbean, but the end re­sult is to­tal dev­as­ta­tion. Li­on­fish are eat­ing/re­pro­duc­ing ma­chines which, at this mo­ment in time, are vir­tu­ally im­pos­si­ble to erad­i­cate.

The WSORC started their li­on­fish re­search project in 2015. The main pur­pose was to record any no­tice­able be­havioural and phys­i­cal changes. They were also look­ing at the sci­en­tific man­age­ment of culling and the ef­fects that li­on­fish have on the lo­cal reefs.

I was in­ter­ested to see how many li­on­fish had in­hab­ited the off­shore reefs so I joined the stu­dents on a sam­ple col­lect­ing day. Kon­rad showed me a long clear plas­tic cylin­dri­cal de­vice called a ‘zoo keeper’ which was used as a li­on­fish con­tain­ment de­vice. A few years ago divers just car­ried a sim­ple net bag! I watched Kon­rad spear a li­on­fish and then push it through the one way rub­ber flap at the end of the cylin­der. I guess this was a safer option and re­duced the risk of get­ting stung.

At least li­on­fish don’t swim off when they are be­ing hunted. I watched Kon­rad lin­ing up an­other shot us­ing a Hawai­ian sling. He took aim while hov­er­ing in a level position. Kon­rad calls it the ‘ninja’ pose. The three pronged spear went straight through the li­on­fish. I was wor­ried that the reef might be dam­aged by way­ward spears but Kon­rad said they make sure it’s dead reef be­hind the li­on­fish. Af­ter two dives the group had caught more than 30 li­on­fish.

As an is­land, Utila is man­ag­ing to con­trol the li­on­fish pop­u­la­tion at most of the pop­u­lar dive sites so it’s quite rare to see them roam­ing about. But when I went on a deeper tech dive (sub 60m) cour­tesy of Utila Dive Cen­tre, I saw quite a few in­di­vid­u­als lurk­ing under ledges. Maybe li­on­fish have re­alised that most recre­ational divers don’t go be­low 40m. The culling has been ap­proved by the Hon­duran gov­ern­ment but divers have to hold an of­fi­cial per­mit.

Ev­ery­body ea­gerly at­tended the af­ter­noon dis­sec­tion ses­sion. All the stu­dents were en­grossed and en­joy­ing the ex­pe­ri­ence. The li­on­fish are weighed and mea­sured be­fore be­ing put under the scalpel. The otolith’s, aka ear bones, are cut off and kept in or­der to iden­tify the age of the spec­i­men. I no­ticed that some of the li­on­fish had su­per oc­u­lar ten­ta­cles and some didn’t, and the sizes seem to vary. Kon­rad revealed that no one knows why they are there. These are also cut off and kept.

Li­on­fish are eat­ing way be­yond their nor­mal life-sus­tain­ing needs, which has led to a no­tice­able in­crease in the amount of fatty tis­sue on each spec­i­men. I didn’t re­alise fish could be fat and un­healthy. Does this mean they are more sus­cep­ti­ble to heart at­tacks? Kon­rad said they would start to weigh the fatty tis­sue and record their find­ings. I watched one of the stu­dents empty a fish’s stom­ach con­tents. Seven ju­ve­nile file­fish were re­moved. The cur­rent record is 69 shrimp from a sin­gle li­on­fish! Data has shown a dra­matic in­crease in phys­i­cal size be­yond all his­tor­i­cal records. Max­i­mum size used to be around the 30cm mark but this has now grown to more than 40cm, with an av­er­age weight of 1kg.

When all the data has been recorded the fil­lets are cut off - li­on­fish are ac­tu­ally very good to eat. Ce­viche seems to be the lo­cal del­i­cacy, which is raw fish ‘cooked’ in lime or lemon juice. The high fat con­tent gives the fish a but­tery flavour.

There seemed to be plenty of other on­go­ing re­search projects at the WSORC. I spoke to Nancy Ar­mas Martinez, who was look­ing at the ef­fects of al­gal growth on lo­cal fish pop­u­la­tions. I watched Nancy lay­ing a tape mea­sure over the reef and then use a Go­pro to record the fish species and coral cov­er­age. This is known as tak­ing line tran­sects and was re­peated at vary­ing depths. The video is an­a­lysed by a spe­cific soft­ware pro­gram and can be used to high­light any sig­nif­i­cant changes. It might not be as ex­cit­ing or ac­tion-packed as whale­sharks or li­on­fish but Utila is lo­cated next to the sec­ond big­gest bar­rier reef in the world, which is ideal for this type of re­search.

I didn’t ex­pect to find a thriv­ing re­search cen­tre so far off the beaten track and I was pleas­antly sur­prised at the range of fa­cil­i­ties on of­fer. There was even an on­site three-man dual lock re­com­pres­sion cham­ber of­fer­ing emer­gency treat­ment and op­er­a­tor train­ing cour­ses. I was also sur­prised to find so many na­tion­al­i­ties, in­clud­ing a fair pro­por­tion of Brits, liv­ing and work­ing on the is­land. (Utila is a pop­u­lar stop on the South Amer­i­can back­packer route). The WSROC is def­i­nitely a solid option for any ma­rine bi­ol­ogy stu­dent or vol­un­teer who wants to learn more about re­search, par­tic­u­larly in­volv­ing whale­sharks. Kon­rad’s work with the wave glid­ers is cut­ting-edge. The eyes and ears of the en­tire whale­shark com­mu­nity are upon him. No pres­sure! I can’t wait to hear about his find­ings. If he can suc­cess­fully track whale­sharks maybe, just maybe, I might have a chance of ac­tu­ally find­ing one next time I visit!

“This has led to a no­tice­able in­crease in the amount of fatty tis­sue on each spec­i­men. I didn’t re­alise fish could be fat and un­healthy”

Divers on a li­on­fish hunt

A $400,000 SHARC wave glider

Utila is fa­mous for its whale­sharks

Diver with a huge li­on­fish

Dis­sect­ing the catch

In the pot

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