Tag: bycatch

Vaquita: a porpoise caught between people and money

By: Alexa Kownacki, Ph.D. Student, OSU Department of Fisheries and Wildlife, Geospatial Ecology of Marine Megafauna Lab

When I first learned of the critically endangered vaquita in early 2015, there were an estimated 97 individuals remaining as reported by CIRVA* (Morell 2014). I was a recent graduate with a bachelor’s degree in Wildlife, Fish, and Conservation Biology, and I, of all people, had never heard of the vaquita. Today, there are an estimated 19 vaquita left (Roth 2019).

Digital painting of a vaquita mother with her calf (Image Source: Aquarium of the Pacific).

The vaquita (Phocoena sinus) is a small porpoise endemic to the Sea of Cortez in the northern region of the Gulf of California, Mexico. It is the most endangered marine mammal and has been for many years, and yet, I had not heard of the vaquita. It wasn’t until I listened to a lunchtime seminar hosted by NOAA Fisheries, that I heard about the porpoise. As a young scientist, “in the field”, I was shocked to realize that I was just learning about an animal, let alone a cetacean, actively going extinct in my lifetime. I believe it’s our job to inform those around us of news in our expertise, and I had failed. I wasn’t informed. As much as I tried in the past four years to describe the decline of the smallest cetacean to anyone who’d listen, I was only reaching a few people at a time. But, today, the vaquita is finally capturing the public’s eye thanks to celebrity support and a feature-length film.

A rare photo of a vaquita (Image Source: Tom Jefferson via the Marine Mammal Center)

From executive producer, Leonardo DiCaprio, comes the Sundance Film Festival Audience Award winner, “Sea of Shadows”. The story of the vaquita truly is an “eco-thriller” and one worth watching. This is not your typical plot line of an endangered species tragically going extinct without action. The vaquita’s story boasts big-name players, such as the Mexican Navy, internationally recognized scientists, Mexican cartels, Chinese mafia, celebrities, the National Marine Mammal Foundation, and Sea Shepherd. At the center of this documentary is the elusive vaquita. The vaquita is not hunted, in fact, this species is not desirable for fisherman. The animal is not aggressive and, in contrast, is notoriously shy, only surfacing to breathe. Furthermore, its name roughly translates into “little cow” because of the rings around its eyes and its docile nature. So, why is this cute creature on the road to extinction? The answer: the wrong place at the wrong time.

“Sea of Shadows” official trailer by National Geographic

The vaquita occupy a small part of the Sea of Cortez where totoaba (Totoaba macdonaldi), a large fish in the drum family, is also endemic. If you’re wondering what a small porpoise and a large fish have in common, then you’d be close to recognizing that is the key to understanding this tragedy. Both species are roughly the same size, one to two meters in length with similar girths. The totoaba, although said to have tender meat, is caught for only one organ: the swim bladder. Now referred to as the “cocaine of the sea”, the dried swim bladders of the totoaba are sold to Mexican cartels who then export the product to China. Once in China, illegal markets sell the swim bladders for up to $100,000USD. Unfortunately, the nets used to illegally catch totoaba, also catch the vaquita. The porpoise has no economic value to the fishermen and therefore are tossed as bycatch. The vaquita is the innocent bystander in a war for money and power.

A man displays the catch from an illegal gillnet, including the totoaba in his arms, and a vaquita, below, that was bycatch (Image Source: Omar Vidal via Aquarium of the Pacific/NOAA Fisheries).

Watching a charismatic species severely decline because of human greed is horrific. The film, however, focuses on the effort of a few incredible organizations that band together in the fight to save the vaquita. Moreover, the multimillion-dollar project, Vaquita CPR, is still ongoing. On a more positive note, in October of 2019, scientists spotted six vaquita during continued conservation and monitoring efforts (Blust & Desk 2019). The path to saving a critically endangered species, especially one that is thought not to do well in captivity, is challenging. The vaquita’s recovery path has many complicated connections which for what appears to be an uphill battle. But, we, the people, are responsible for this. We must support research and conservation by using our voice to share what is happening, for a porpoise and for the world.

*Comité Internacional para la Recuperación de la Vaquita (International Committee for the Recovery of the Vaquita)

Citations:

Blust, Kendal, and Fronteras Desk. “Photo Sparks Increased Concern over Fishing in Vaquita Refuge.” Arizona Public Media, 25 Oct. 2019, https://news.azpm.org/p/news-topical-nature/2019/10/25/160806-photo-sparks-increased-concern-over-fishing-in-vaquita-refuge/.

Morell, Virginia. “Vaquita Porpoise Faces Imminent Extinction-Can It Be Saved?” National Geographic, 15 Aug. 2014, https://www.nationalgeographic.com/news/2014/8/140813-vaquita-gulf-california-mexico-totoaba-gillnetting-china-baiji/.

Roth, Annie. “The ‘Little Cow’ of the Sea Nears Extinction.” National Geographic, 17 Sept. 2019, https://www.nationalgeographic.com/animals/2019/09/vaquita-the-porpoise-familys-smallest-member-nears-extinction/#close.

Knowing me, knowing you: the fate of the toninha, a small dolphin endemic to the Western South Atlantic

By Salvatore Siciliano (1,2)

(1) Laboratório de Enterobactérias, Oswaldo Cruz Institute/Fiocruz, Rio de Janeiro, Brazil
(2) Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos (GEMM-Lagos)

 

 

Background information on Pontoporia blainvillei

The toninha (Pontoporia blainvillei) as it is called in Brazil, or franciscana (Fig.01), is a small dolphin endemic to coastal waters of southeastern and southern Brazil, Uruguay and Argentina. It is the only representative of an ancient lineage of odontocetes, once widely spread over the Pacific and Atlantic oceans. Toninhas occur in waters shallower than 30 m and present a discontinuous distribution from Itaúnas, Brazil (18º 25’S) to Golfo San Matías, Argentina (42º 10’S). The species is considered one of the most threatened small cetaceans in South America due to high, and possibly unsustainable, bycatch levels as well as increasing habitat degradation. Incidental catches in fishing gear, especially gillnets and trammel nets, have been reported along most of the species’ range since at least the 1940s. Other rapidly-increasing conservation issues of significant importance for the franciscana in this region include: (1) habitat degradation, (2) underwater noise, (3) chemical pollution from industrial and urban wastewater, (4) activities related to the exploration and production of oil and gas, and (5) vessel traffic. P. blainvilleiis currently listed as ‘Vulnerable’ in the IUCN Red List of Threatened Species and ‘Critically Endangered’ by the Brazilian Government.

 

Figure 01: A young Pontoporia blainvillei incidentally caught in gillnets set off the northern coast of the state of Rio de Janeiro, Brazil (December 2011).

 

In order to guide conservation and management actions on a regional basis, the franciscana range was divided into four zones, known as ‘Franciscana Management Areas’ (FMAs), in the early 2000s. FMA I includes Espírito Santo (ES) and northern Rio de Janeiro (RJ), states located in southeastern Brazil. FMA II corresponds to southern RJ, São Paulo (SP), Paraná (PR) and northern Santa Catarina (SC) states, in southeastern and southern Brazil. FMA III encompasses southern SC and Rio Grande do Sul (RS) states, in southern Brazil, in addition to Uruguay. The last FMA, the FMA IV, corresponds to the Argentina coast (Fig.02).

The absence of stranded or incidentally killed animals indicates a gap of approximately 320 km in the franciscana distribution between northern and southern RJ. This gap separates the southern border of FMA I and the northern border of FMA II.

 

Figure 02: The FMA areas (in blue) in P. blainvillei distribution range, and the gaps (in white) in toninha distribution along the Northern limit of its distribution in Southeastern Brazil.

 

The toninha is usually very shy and, for this reason, quite difficult to be seen in the wild. More recently, researchers and citizen science projects have succeeded in obtaining very nice pictures of these animals (Fig.03), which are aiding in elucidating the species mysterious behavior, feeding activity and their preferred habitat conditions.

Figure 03: Toninhas in their natural environment along shallow waters off northern São Paulo state, in the summer of 2019. Photo courtesy of Júlio Cardoso, Baleia à Vista Project.

 

Figure 04: Aerial view of the Restinga de Jurubatiba National Park and its adjacent waters, the main toninha habitat along the northern coast of Rio de Janeiro. Photo by Salvatore Siciliano (November 2017).

 

Threats to P. blainvillei along the Brazilian coast

Gillnets are still the main cause of toninha mortality along its entire range. They can be used at the surface or placed at the bottom of the ocean to catch fish, but these nets also entangle this small dolphin (Fig.05, Fig.06).

Figure 05: Gillnets, used at the surface or placed at the bottom of the ocean.

 

Figure 06: Data on gillnet incidental captures of toninhas (Pontoporia blainvillei) along the northern coast of Rio de Janeiro state collected since1988. Note the concentration of records in the Macaé – Quissamã and Cabo de São Thomé areas, adjacent to the Restinga de Jurubatiba National Park. Data on captures come from Prof. Ana Paula M. Di Beneditto/CBB/LCA/UENF.

 

Toninhas also face other threats along the Brazilian coast, including environmental chemical contamination by metals and persistent organic pollutants. These pollutants are persistent in the aquatic ecosystem and may accumulate and magnify throughout the tropic chain, causing deleterious effects in the aquatic fauna. Recently, an ecotoxicological assessment from our research group (GEMM-Lagos/Fiocruz) verified, for the first time, significant intracellular concentrations of several toxic metals, such as Hg and Pb (Fig.07), in P. blainvillei individuals sampled along the coast of the Rio de Janeiro state.

 

Figure 07: Novel HPLC-ICP-MS data on intracellular Pb and Hg in P. blainvillei liver (L), muscle (M) and kidney (K) samples from stranded individuals sampled off the coast of Rio de Janeiro, Brazil.

 

The monitoring of the contaminant levels in toninhas will potentially aid in conservation efforts, as we can identify which metals are of the most concern, because the intracellular presence of toxic metals indicates high bioavailability, probably leading to deleterious effects.

 

Conservation Efforts

What is a Whale Heritage Site (WHS) and why we are proposing ‘Mosaic Jurubatiba’ as a WHS?

Situated on the Northern coast of Rio de Janeiro state, Brazil, the Jurubatiba region (Fig.04; Fig.08) is now a Candidate Whale Heritage Site (WHS). The area has been termed ‘Mosaic Jurubatiba’ as the candidate site includes not only the Jurubatiba National Park, but also encompasses other significant sites for conservation along the central-north coast that lie across three municipalities: Macaé, Carapebus and Quissamã (Fig.08).

Figure 08: Proposed extension of the Jurubatiba National Park to the adjacent waters, home of a vigorous population of P. blainvillei.
Legend: green – Jurubatiba National Park; red – new terrestrial limit; yellow – new marine limit.

 

The location provides habitat to a diversity of wildlife. When considering cetaceans, the most regularly seen individuals are the humpback whales, the Guiana dolphins and the toninhas. This is an important site since it is part of the migration route of humpback whales from their breeding and calving grounds, in warm tropical waters, to their feeding grounds, in Antarctica. In addition, this locality is a significant habitat for the toninha, a restricted range species, and the Guiana dolphin, a data deficient species and, therefore, of great concern. The importance of the site becoming a fully accredited WHS is, therefore, evident to further conserve these species and their habitats.

There is a significant amount of active conservation in the Jurubatiba National Park. The Park is the first to exclusively comprise the Restinga ecosystem. Researchers worked alongside authorities and large organizations, such as IBAMA (Brazilian Ministry of Environment and the federal government), to achieve its national park status.

Figure 09: Outreach material produced for the campaign ‘Mosaic Jurubatiba’ to promote education and conservation of the Toninha.

 

In Quissamã, warning signs were placed along the beaches to alert the population of the importance of the coastal waters as habitat for dolphin species, especially the toninha. This type of cooperation and support of the government and other authorities will aid the candidate site to achieve a full status of WHS.

The long-term goals of the candidate site are to influence the transition away from fishing as a livelihood and to instead embrace the use of responsible tourism to make a living.

 

For more information on Whale Heritage Sites around the world, visit:

http://worldcetaceanalliance.org/

http://whaleheritagesites.org/candidate-site-jurubatiba/

 

For more information on the GEMM-Lagos Project:

contact:gemmlagos@gmail.com

visit their Instagram: toninha_cade_vc

 

Here you can also find a list of some of the Salvatore Siciliano’s publications on Pontoporia blainvillei:

  • Siciliano S, de Moura JF, Tavares DC, Kehrig HA, Hauser-Davis RA, Moreira I, Lavandier R, Lemos LS, EMin-Lima R, Quinete N. 2018. Legacy Contamination in Estuarine Dolphin Species From the South American Coast. In book: Marine Mammal Ecotoxicology. Eds. Fossi MC, Panti C. Publisher: Academic Press.
  • Baptista G, Kehrig HA, Di Beneditto APM, Hauser-Davis RA, Almeida MG, Rezende CE, Siciliano S, de Moura JF and Moreira I. 2016. Mercury, selenium and stable isotopes in four small cetaceans from the Southeastern Brazilian coast: Influence of feeding strategy. Environmental Pollution 218:1298-1307.
  • Frainer G, Siciliano S, Tavares DC. 2016. Franciscana calls for help: the short and long-term effects of Mariana’s disaster on small cetaceans of South-eastern Brazil. International Whaling Commission SC/66b/SM/04. Bled, Slovenia.
  • Lavandier R, Arêas J, Quinete N, de Moura JF, Taniguchi S, Montone RC, Siciliano S, Moreira I. 2015. PCB and PBDE levels in a highly threatened dolphin species from the Southeastern Brazilian coast. Environmental Pollution 208.
  • Lemos LS, de Moura JF, Hauser-Davis RA, de Campos RC, Siciliano S. 2013. Small cetaceans found stranded or accidentally captured in southeastern Brazil: Bioindicators of essential and non-essential trace elements in the environment. Ecotoxicology and Environmental Safety 97:166-175.
  • de Moura JF, Rodrigues ES, Sholl TGC, Siciliano S. 2009. Franciscana dolphin (Pontoporia blainvillei) on the north-east coast of Rio de Janeiro State, Brazil, recorded during a long-term monitoring programme. Marine Biodiversity Records 2:e66.