NEW STUDY BY MORIGENOS ON TOXIC POLLUTANTS IN DOLPHINS

New research shows that dolphins in the northern Adriatic contain high levels of PCBs, highly toxic chemicals banned in the 1970s-1980s, and that females pass on their pollutant burden to their young. A new study led by Morigenos was published yesterday in the journal Science of the Total Environment.

PCBs (polychlorinated biphenyls) are a group of man-made chemicals previously used in the manufacture of products including electrical equipment, flame retardants and paints. High exposure to PCBs is known to weaken animal immune systems and markedly reduce breeding success by causing abortions or high mortality in newborn calves. Even though their use has been banned for three decades, they are still present in the marine environment, and particularly in top marine predators such as dolphins.

An international team of researchers, led by Morigenos, evaluated PCB and other organochlorine contaminants in bottlenose dolphins (Tursiops truncatus) living in the Gulf of Trieste (northern Adriatic Sea), the northernmost part of the Mediterranean Sea and one of the most human-impacted areas in the Mediterranean. Apart from Morigenos, the study involved the Sea Mammal Research Unit at the University of St Andrews (UK), Zoological Society of London’s Institute of Zoology (UK), Centre for Environment, Fisheries and Aquaculture Science (CEFAS, UK) and the Institute of Marine Sciences of the Italian National Research Council (Italy).

Overall, 87.5% of dolphins had PCB concentrations above the toxicity threshold for the onset of physiological effects in marine mammals, while 65.6% had concentrations above the highest threshold published for marine mammals based on reproductive impairment in seals. Such high contaminant levels are of concern particularly in combination with other threats to dolphins, including bycatch in fisheries, disturbance by boat traffic, marine litter, prey depletion, etc.

“We have been studying these dolphins for over 16 years, so we know most of them well. Through long-term re-sighting histories of identified individuals, we were able to link PCB levels in individual dolphins to parameters such as sex, reproductive output and social group membership.” said Tilen Genov from Morigenos, the lead author of the study and a PhD student at the University of St Andrews, UK.

The research showed that males have significantly higher pollutant concentrations than females. This is because females offload a substantial amount of their toxicological burden to their young through gestation and lactation. That is also why females that have not yet had calves had significantly higher concentrations than those that had previously produced at least one calf. Such results are expected based on our knowledge of mammal physiology, but it is not very common to demonstrate this phenomenon in wild whales and dolphins.

Dead animals stranded on shore are typically used for pollutant studies, but with such samples, one never knows exactly where and how the animals lived before washing up on shore. Furthermore, the decomposition may alter the pollutant concentrations in the tissues. On the other hand, because obtaining samples from live animals is not easy, many long-term observational studies of dolphins lack information on pollutants. Here, researchers were able to combine these two important aspects, as samples were collected from live dolphins of known identities, without capturing or harming them. While this isn’t the first research to do that, such studies remain relatively rare, especially in the Mediterranean Sea, the largest enclosed sea in the world, with substantial human pressure. With the largest sample size of live free-ranging animals in the Mediterranean Sea or Europe published for this species to date, this study provides valuable new information on pollutants in dolphins.

Dr Paul Jepson, co-author of the study and specialist wildlife veterinarian at Zoological Society of London’s Institute of Zoology, said: “This is another study showing high or very high levels of a very toxic and persistent pollutant – PCBs – in European dolphins. PCBs have the ability to cause diseases like cancer and can also suppress reproduction.”

Morigenos has been studying dolphins in the Gulf of Trieste and adjacent waters since 2002, looking at their population size and distribution, behaviour, social and genetic structure, and the effects of human activities on them.

Tilen Genov: “Our previous research has also shown that these dolphin form distinct social groups, which behave differently and may have different diets. This implied that the amount of pollutants they accumulate may also differ because of the different food they eat. However, this study showed that they are all equally contaminated, regardless of potential differences in what they eat, and that PCBs are a problem for all of them.”

Dr Paul Jepson: “The wider context is that much more needs to be done - across European countries - to clean-up the major sources of PCBs entering the marine environment. The Mediterranean Sea has some of the highest PCB exposures globally in dolphins and other wildlife species.”

The paper is freely available at the following link: https://authors.elsevier.com/a/1YBpcB8ccghjk

NOVA RAZISKAVA DRUŠTVA MORIGENOS O TOKSIČNIH SPOJINAH V DELFINIH

Nova raziskava je pokazala, da imajo delfini v severnem Jadranu v svojih telesih visoke vsebnosti PCBjev, izredno toksičnih spojin, prepovedanih že od 70. in 80. let, in da samice svoje strupeno breme prenašajo na svoje mladiče. Nova raziskava pod vodstvom društva Morigenos je bila včeraj objavljena v ugledni mednarodni reviji Science of the Total Environment.

Poliklorirani bifenili oz. PCB spojine so skupina umetnih kemikalij, ki so se nekoč uporabljale pri izdelavi različnih izdelkov, vključno z električno opremo, zaviralci gorenja in barvami. Gre za eno najbolj toksičnih snovi, kar jih je ustvaril človek. Znano je, da visoka izpostavljenost PCB spojinam pri živalih povzroča oslabitev imunskega sistema in znatno zmanjšano rodnost. Slednja se lahko izraža kot povečano število splavov ali kot visoka smrtnost novorojenih mladičev. 

Mednarodna ekipa znanstvenikov pod vodstvom društva Morigenos je ugotavljala prisotnost PCB in drugih kemičnih spojin v velikih pliskavkah (Tursiops truncatus), ki živijo v Tržaškem zalivu in okoliških vodah severnega Jadrana, najsevernejšem delu Sredozemskega morja in enem od najbolj obremenjenih območij v celotnem Sredozemlju. V raziskavi so poleg društva Morigenos sodelovali še Univerza St Andrews (Velika Britanija), Zoološki inštitut Zoološkega društva v Londonu (Zoological Society of London, Velika Britanija), Center za znanosti o okolju, ribištvu in akvakulturi (CEFAS, Velika Britanija) in Inštitut za morske znanosti Italijanskega nacionalnega sveta za raziskave (Italija).

Vsega 87.5% delfinov je imelo PCB koncentracije nad pragom toksičnosti, kjer pride do fizioloških vplivov pri morskih sesalcih, medtem ko jih je 65.6% imelo koncentracije nad pragom, za katerega je bilo ugotovljeno, da vodi v nesposobnost razmnoževanja pri morskih sesalcih. Takšne visoke vsebnosti onesnaževal so zaskrbljujoče predvsem v kombinaciji z drugimi grožnjami kot so naključni ulov v ribiške mreže, vpliv pomorskega prometa, onesnaženje s plastiko, pomanjkanje plena, ipd.

“Te delfine preučujemo in spremljamo že 16 let, zato večino zelo dobro poznamo. S pomočjo dolgoletnih podatkov o opažanjih posameznih identificiranih delfinov smo lahko koncentracije onesnaževal povezali z različnimi parametri kot so spol, rodnost in pripadnost določenim socialnim skupinam.” je povedal Tilen Genov iz društva Morigenos, vodilni avtor raziskave in doktorski študent na Univerzi St Andrews iz Velike Britanije.

Raziskava je pokazala, da imajo samci bistveno višje koncentracije onesnaževal kot samice. Do tega pride, ker samice velik del svojega toksikološkega bremena prenesejo na mladiče v času brejosti in dojenja. To je tudi razlog, da imajo samice, ki še niso imele mladičev, bistveno višje koncentracije kot samice, ki so že imele vsaj enega mladiča. Takšni rezultati so glede na naše poznavanje fiziologije sesalcev sicer pričakovani, vendar je ta pojav razmeroma redko moč prikazati pri prostoživečih kitih in delfinih.

Za študije prisotnosti onesnaževal se navadno uporablja vzorce poginulih živali, ki jih naplavi na obalo. Toda pri tovrstnih vzorcih se nikoli ne ve, od kod poginule živali izvirajo ter kje in kako so živele pred smrtjo. Prav tako lahko proces razpadanja spremeni koncentracije onesnaževal v tkivih. Po drugi strani pa večina dolgoročnih terenskih raziskav živih delfinov ne vključuje informacij o onesnaževalih, saj je pridobivanje vzorcev živih živali težavno. V tej raziskavi pa so raziskovalci združili ta dva pomembna vidika, saj so pridobili vzorce živih živali, ki jih že leta spremljajo. Čeprav to ni prva raziskava, ki je ta dva vidika uspešno združila, so tovrstne raziskave v svetu še vedno razmeroma redke, predvsem v Sredozemskem morju, ki velja za največje polzaprto morje na svetu, z občutnimi človeškimi pritiski. Ta raziskava predstavlja doslej največje število analiziranih vzorcev živih prostoživečih velikih pliskavk v Sredozemlju in Evropi ter prispeva pomembne nove informacije o onesnaževalih v delfinih.

Dr. Paul Jepson, so-avtor raziskave in veterinarski specialist za prostoživeče živali pri Zoološkem inštitutu Zoološkega društva v Londonu, je dejal: “To je še ena raziskava, ki kaže visoke ali zelo visoke nivoje izredno toksičnih in obstojnih onesnaževal – PCB spojin – v evropskih delfinih. PCB spojine lahko povzročajo bolezni kot je rak in tudi onesposobijo zmožnost razmnoževanja.”

Društvo Morigenos delfine v Tržaškem zalivu in okoliških vodah preučuje od leta 2002, s poudarkom na raziskavah velikosti in razširjenosti populacije, vedenja, socialne in genetske strukture ter vplivov človeških aktivnosti na delfine.

Tilen Genov: “Naše predhodne raziskave so pokazale, da ti delfini tvorijo več ločenih socialnih skupin, ki se različno obnašajo in imajo morda celo različno prehrano. To bi lahko pomenilo, da se tudi količina onesnaževal, ki jo kopičijo v telesih, med skupinami razlikuje zaradi razlik v prehrani. Toda ta raziskava je pokazala, da so vsi enako obremenjeni z onesnaževali in da so PCB spojine problem za celotno populacijo.”

Dr. Paul Jepson: “Širši kontekst tega je to, da je potrebno narediti še ogromno – v vseh evropskih državah – da se počisti glavne vire PCB spojin, ki vstopajo v morsko okolje. Delfini in druge morske živali v Sredozemlju imajo izredno visoko izpostavljenosti PCB spojin, med najvišjimi na svetu.”

Članek je prosto dostopen na naslednjem naslovu: https://authors.elsevier.com/a/1YBpcB8ccghjk

ADOPT A DOLPHIN FROM THE SLOVENIAN SEA - A WONDERFUL GIFT FOR THE HOLIDAYS

Give your loved ones interesting and useful gift for upcoming holidays: adopt a dolphin from Slovenia and support conservation of dolphins and their environment in the northern Adriatic.

By adopting a dolphin you financially support the research of marine mammals in Slovenia and the northern Adriatic.

With the donation for the one-year dolphin adoption, you will financially support our work and thus contribute to the conservation of the northern Adriatic and its biodiversity.

Every adopter receives an adoption certificate which includes: the adopter’s name, the name of the dolphin, a biography of the chosen dolphin with his best photos (all in English language). Adopters will also receive a gift: a Morigenos T-shirt and a postcard.

For more informations go to: https://www.morigenos.org/en/adopt-a-dolphin/

POSVOJITE DELFINA IZ SLOVENSKEGA MORJA - ČUDOVITO DARILO ZA PRAZNIČNE DNI

Obdarujte svoje najbližje z zanimivim in koristnim darilom: posvojite delfina iz slovenskega morja in podprite varstvo delfinov in njihovega okolja v severnem Jadranu.

Z donacijo, ki jo prispevate za enoletno posvojitev delfina, finančno podprete delo društva Morigenos in s tem pripomorete k ohranjanju našega morja in njegove biotske raznovrstnosti.

Vsak posvojitelj prejme certifikat o posvojitvi z njegovim in delfinovim imenom ter življenjepis izbranega delfina z njegovimi najboljšimi fotografijami. Posvojitelji prejmejo tudi majico in razglednico društva Morigenos.

Več informacij najdete na: https://www.morigenos.org/posvojite-delfina-iz-slovenskega-morja/

SUPPORT A GOOD CAUSE

Help us achieve our goals! Morigenos and its effort for the conservation of dolphins and healthy marine ecosystems has been chosen for the Slovenian partner of the action #VEDNOPODPIRAJ DOBER NAMEN (ALWAYS SUPPORT A GOOD CAUSE), organised by Coca-Cola. Within the action, they will financially support three socially responsible Slovenian projects working on the topics of sports, environment and community. We would truly appreciate your support through giving us your vote and sharing this among your friends! Follow the link and click on ODDAJ SVOJ GLAS (GIVE YOUR VOTE) for Morigenos. You can vote as many times as you want, until 31 December 2018. Each vote counts. Thank you for your support!

You can vote here.

PODPRITE DOBER NAMEN

Pomagajte nam pri uresničitvi naših ciljev! Društvo Morigenos in njegovo prizadevanje za varstvo delfinov in zdravih morskih ekosistemov je bilo izbrano za slovenskega partnerja akcije #VEDNOPODPIRAJ DOBER NAMEN, ki jo organizira podjetje Coca-Cola. V okviru akcije bodo finančno podprli tri družbeno odgovorne slovenske projekte na področjih športa, okolja in skupnosti. Zelo hvaležni vam bomo, če za društvo Morigenos oddate svoj glas in k sodelovanju preko svojih omrežij povabite tudi prijatelje! Glasujete lahko večkrat, vse do 31. decembra 2018. Vsak glas šteje, saj boste s tem tri projekte z največ prejetimi glasovi pomagali uresničiti. Hvala za vašo podporo!

Glasujete lahko tukaj.

Skrivnostni svet delfinov - otvoritev fotografske razstave

Kdaj: 24.11.2018 ob 18.00 uri

Kje: galerija Apolonijeve palače (Župančičeva ulica 7, Piran)

*Dogodek je finančno podprla Občina Piran.

SLOVENIA TAKES OVER THE PRESIDENCY OF THE INTERNATIONAL WHALING COMMISSION

Last week marked the end of the biennial 67th meeting of the International Whaling Commission (IWC) in Florianopolis, Brazil, where Slovenian took over the 2-year presidency of the Commission from Japan. The International Whaling Commission was set up based on the Convention for the Regulation of Whaling, signed in Washington on 2 December 1946. Slovenia became a member of the IWC in 2006. IWC member states are divided to those that oppose different types of whaling (“like-minded or anti-whaling countries”, which includes Slovenia) and those that support whaling (“countries for the sustainable use of whales or pro-whaling countries”). The IWC mainly decides on the whaling quotas and strategies for their conservation. The aim of the Convention itself is the regulation of whaling, rather than prevention of it. Nevertheless, in 1982 the IWC placed a moratorium (ban) on commercial whaling, which brought some whale species to the brink of extinction. Some types of whaling are still allowed under certain circumstances, for example the aboriginal subsistence whaling that allows local tribes or communities to carry out traditional whaling for their own consumption. Two more types of whaling are being carried out, outside the scope of the IWC. The first is the “scientific whaling”, allowed by the Convention, but carried out under the exclusive jurisdiction of member countries. This type of whaling is carried out by Japan. The second type of whaling is the one under the objection to the moratorium, used by Iceland and Norway.

SLOVENIJA PREVZELA PREDSEDOVANJE MEDNARODNI KOMISIJI ZA KITOLOV

V brazilskem Florianopolisu se je ta konec tedna zaključilo bienalno 67. zasedanje Mednarodne komisije za kitolov (IWC), kjer je Slovenija zadnji dan zasedanja od Japonske prevzela dvoletno predsedovanje komisiji. Mednarodna komisija za kitolov je nastala na podlagi Mednarodne konvencije o ureditvi kitolova, ki je bila podpisana v Washingtonu 2. decembra 1946. Republika Slovenija je pogodbenica komisije od leta 2006. Države pogodbenice se delijo na tiste, ki se zavzemajo za popolno ali delno prepoved različnih vrst kitolova (“skupina podobno mislečih držav”, kamor spada Slovenija) ter tiste, ki temu nasprotujejo (“skupina za trajnostni kitolov”) in si prizadevajo za uveljavitev določenih oblik kitolova. Komisija odloča predvsem o kvotah za ulov kitov in ukrepih za njihovo varstvo. Temeljni namen konvencije je ureditev in ne prepoved kitolova, kljub temu pa je Komisija leta 1982 sprejela moratorij, s katerim je ustavila komercialni kitolov, ki je v preteklosti nekatere vrste kitov pripeljal na rob izumrtja. Pod določenimi pogoji je še vedno dovoljen kitolov, ki ga izvajajo domorodna ljudstva za namene samooskrbe. V praksi se izvajata še dve obliki kitolova, ki sta izven nadzora Komisije. Prva je t.i. “znanstveni kitolov”, ki ga omogoča sama Konvencija, njegovo izvajanje pa je v izključni pristojnosti držav pogodbenic. To vrsto kitolova izvaja Japonska. Druga oblika kitolova je uveljavitev pridržka na moratorij, kar izrabljata Islandija in Norveška. Kljub imenu pa kitolov ni več edini ali glavni predmet dela komisije, saj le-to danes vključuje mnoge vidike raziskovanja in varstva kitov in delfinov, npr. preprečevanje neželenega ulova v ribiško opremo ter trčenj kitov z ladjami, problematiko onesnaženja ter drugih groženj kitom in delfinom. Komisija je tako v svetovnem merilu eno izmed osrednjih mednarodnih teles za vprašanja raziskovanja in varstva kitov in delfinov. Društvo Morigenos oz. njegovi člani v delu komisije sodelujejo predvsem kot aktivni člani Znanstvenega odbora.

DELFINI SE PODPIŠEJO Z ŽVIŽGOM

Delfini se podpišejo z žvižgom Jata velikih pliskavk, ki se zadržuje v slovenskem morju, je posebna tudi v svetovnem merilu

Oglejte si naš prispevek v časopisu Delo in poizvejte zelo zanimive informacije o delfinih v Jadranu. Priporočamo.

KLIKNITE TUKAJ ZA POVEZAVO DO PRISPEVKA