20 April 2017

Last Stretch Towards Saving the 30 Vaquitas



They ought to stay, these beautiful, shy vaquitas (Phocoena sinus), but the possibility of seeing them in our lifetime is immensely threatened. They are on the edge of extinction.

Vaquitas ("little cow" in Spanish), the world's smallest cetaceans, belong to the family Phocoenidae, the porpoises, which contains only 6 species worldwide. They can reach a length of up to 1.5 meters, and can only be found in Mexico's Gulf of California [1].

They live in murky, relatively shallow waters, feeding on various demersal and benthic fishes. Although they can be spotted in small groups, up to 10 individuals, they can be loosely aggregated across a wide expanse of water [2].

We are fascinated as we are intrigued by a dolphin's inherent "smile". Vaquitas are kindred to this anatomical configuration: with inward black lips and dark circles around their eyes, shaded like a mascara. Unlike delphinids which have conical teeth, porpoises have compressed, spatulate teeth [3].

Photo from Pinterest

While there used to be 567 individuals in the region (a best estimate in 1997) [2,4], a survey in November 2016 stated that there are only around 30 of them left - a staggering 95% decline in their population [4]. Left unprotected, the species may be forever gone by 2020 [7].

And we might lose them in exchange for soup.


Entangled for Too Long

The vaquita's population has always been precarious [9]. Often drowning from bycatch, the porpoise was decimated in 2015 by gill nets used to catch another critically endangered species, the totoaba (Totoaba macdonaldi).

The fish, reaching 2 meters and weighing as much as 100 kg [5], is priced merely for its swim bladder which it uses for buoyancy [4,6]. The organ is remarkably reputed by the Chinese to cure many ailments and boost fertility - ultimately brewing as soup called fish maw [7].

Hunting for this enticing fish has been illegal since 1975. But, like drugs, the market holds too strong an incentive for this lucrative 'commodity', earning its title the "aquatic cocaine" [6]. The giant bladder - with its unusual 'tentacles' - bags around $10,000 each in Chinese black markets [7].

Totoaba's huge bladder is prominent with its two, dangling  tentacles (Photo from CNN

In April 2015, the Mexican government enforced a two-year ban on all gill nets across the species' niche, covering 11,595 square kilometers [6]. Millions of dollars were spent compensating local fishermen not to fish in the region, along with regular military surveillance. Conservationists also participated in this huge endeavor to save the vaquitas in the wild [8].

Despite incremental efforts, the situation hit rock-bottom.

As the market for totoaba had only proved grueling, two more vaquitas, lifeless ashore, were spotted in March [9]. 59 individuals existed in 2015 but now a mere 30 breathe [4]. More recently, on the lookout for poachers, the Sea Shepherd group exposed hundreds of illegal gill nets ready to hunt the totoabas, ready to drown the vaquitas [9].

Photo by Flip Nicklin

The ocean, its supposed sanctuary, has transformed into an inescapable trap. Omar Vidal, the CEO of WWF-Mexico, probably said it best: "We can still save the vaquita, but this is our last chance." [8].


The Audacious Plan

Some of the porpoises are bound to be rescued in October this year. The Mexican government has given US $3 million to the Vaquita CPR. Along with it, an international organization, Association of Zoos and Aquariums, donated $1 million [4].

Although acoustic data are available for preliminary detection, vaquitas are difficult to spot. They may wander alone or in pairs. Consequently, the plan to save them will rely on two US Navy trained dolphins to echo-locate their cetacean kin within the 2000 plus square kilometer home range [4]. However, scientists are concerned whether they can find them, let alone catch them without complications [9].

Also, scientists distill doubts in bringing them to captivity. The move poses high risks as no studies have been done to ascertain their survival [4]. They just don't know how the vaquitas will behave. And, even in the best of conditions, breeding in captivity is deemed unlikely to restore the population [9].

Still, some are hopeful that the plan could work [4]. Huge, dramatic measures will be considered in advance for the rescue. For instance, tissue culture can be secured for future studies. Also, veterinarians and captivity experts will board the mission and make certain that if vaquitas are stressed, the mission will be instantly called off. New plans will be conceived [6].

Saving the vaquitas remains to be an arduous battle. Securing them in a sanctuary may be the first bold step.

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[1] Palomares, M.L.D, & Pauly, D (eds). 2017. SeaLifeBase. World Wide Web electronic publication. www.sealifebase.org, version (02/2017).

[2] Rojas-Bracho, L., Reeves, R.R., Jaramillo-Legorreta, A., & Taylor, B.L. 2008. Phocoena sinus. The IUCN Red List of Threatened Species 2008: e.T17028A6735464. Retrieved from http://bit.ly/2pzpE3i

[3] Berta, A. (Eds.) (2015). Whales, dolphins, and porpoises: a natural history and species guide. University of Chicago Press.

[4] Nicholls, H. (2017, April 7). Last-ditch attempt to save world's most endangered porpoise gets go-ahead. Nature. Retrieved from http://go.nature.com/2oMJBDn

[5] Froese, R., & Pauly, D. 2017. FishBase. World Wide Web electronic publication. www.fishbase.org, version (02/2017).

[6] Holman, J. (2017, April 12). Features: The race to save Mexico's vaquita from extinction. AlJazeera. Retrieved from http://bit.ly/2oTZlnK

[7] Joyce, C. (2016, February 9). Chinese taste for fish bladder threatens rare porpoise in Mexico. NPR. Retrieved from http://n.pr/1Kawdz5

[8] Bale, R. (2016, May 16). World's smallest porpoise is on the verge of extinction. National Geographic. Retrieved from http://bit.ly/24UPdHX

[9] Malkin, E. (2017, February 27). Before vaquitas vanish, a desperate bid to save them. The New York Times. Retrieved from http://nyti.ms/2l71NGZ





29 March 2017

Benham Rise: A Call For Connectivity and Action



Beyond The Journey

Benham Rise, an undersea territory, is located east of Luzon where its shallowest part, Benham Bank, is at least 50 meters deep. Its name originated from the surveyor Andrew Benham who first mapped the region in 1933 [2].

April 12, 2012 marks the United Nations Commission on the Limits of the Continental Shelf (UNCLCS) validating the additional 13-million hectare extended continental shelf (ECS) of Benham Rise as part of the Philippines' continental shelf. Now, our maritime rights on the region stretched from the original 11.4 million hectares (within the 200 nm Exclusive Economic Zone) to 24.4 million hectares, nearly equal to our land expanse - currently at 30 million hectares [1, 2].

What is clear here is that Benham Rise is not considered a part of the Philippine national territory but the country is bestowed "sovereign rights" (less than "sovereignty") over the region, allowing it exclusive and superior authority to explore, develop and utilize its living and non-living resources [4]. 

Map of Benham Rise showing the acquired extended continental shelf (ECS).

It could have been a viewed as swift success. The claim, however, was pursued tenaciously, thanks to over a decade worth of work by a team of public servants, scientists and legal experts. What was once a workshop in 2001 forged the first major successful claim under the United Nations Convention on the Law of the Sea (UNCLOS) [1].


Recent Glimpse

Last May 2016, Oceana, Earth's NGO solely for marine conservation, joined government scientists from the Bureau of Fisheries and Aquatic Resources (BFAR), University of the Philippines, Philippine Coast Guard and Philippine Navy on an expedition in Benham Bank. They did oceanographic, benthic (study of the seabed) and microbiological surveys, and documented large marine life [1].

They were thrilled to discover 100% coral cover in the surveyed area, which, if highly unlikely, is rare in the Philippines. According to Oceana’s Marine Scientist, Marianne Pan Saniano, the bank had crystal clear waters (personal communication, March 23, 2017). Rightfully so, the team reported the bank to hold a diverse, multitude of marine organisms [2].


The Twilight's Promise

The team documented at 50 m depth a huge ‘mesophotic’ or deep-sea reef ecosystem laden with impressive coral cover and associated fauna.


A colony of foliose corals at a minimum depth of 50 meters in Benham Bank. (Oceana / UPLB)


As shallow water reefs continue to degrade, scientists turn their hopes to the mesophotic zone. It’s also called the “twilight zone” as it signifies the transition between brightly lit surface waters and dark, deeper depths. The mesophotic zone (30-150 m) is often deemed as extensions of shallow-water reef ecosystems, dominated by light-dependent corals, sponges and algae [6].

Though widespread and diverse, mesophotic coral ecosystems (MCEs) remain largely unexplored. The good news, though, is that new technologies allow deeper exploration of our oceans.

One hypothesis that incited the interest of studying the mesophotic zone is the ‘deep reef refugia’ hypothesis which underscores its potential for replenishing  or “re-seeding” damaged reef ecosystems [6]. In one study, MCEs, seagrass beds and mangroves are found to likely to provide brood stocks - replenishing and sustaining damaged, heavily exploited nearshore reefs. Such was the case in the spawning aggregations of the red hind grouper (Epinephelus guttatus) which re-seeded shallow waters when it produced larvae in deep waters off US Virgin Islands [10].

Studies in the Indo-Pacific MCEs have also shown the region to hold diverse benthic communities. They also serve as refuge to shallow-water coral reef species experiencing environmental stress like light-enhanced warm water bleaching [9].

Using an autonomous underwater vehicle (AUV), scientists surveyed, at depths of 50 to 65 m, anemonefishes at Viper Reef and Hydrographers Passage in the Great Barrier Reef. The findings show that at least some species of host sea anemones and anemonefishes occur across a wider bathymetric range, stretching from reef flats and slopes into the mesophotic zone. This supports the hypothesis that mesophotic reefs contain many species only thought to be common to shallow-water reef habitats [8].

Over the years, the idea of the zone’s emerging importance has taken momentum. Take Papahanaumokuakea Marine National Monument in Hawaii where divers used mixed-gas dives. The study revealed that its mesophotic reefs host an unprecedented rate of endemism. At depths of 30 to 90 m, about 46% of reef fishes are endemic, significantly higher than previous shallow water surveys in the area, and almost two-fold higher than in any other tropical region [7].

It is possible to unearth high endemism rates as well in other protected, uncharted mesophotic regions such as that of Benham Rise, suggesting the importance of spreading awareness of its existence. 

MCE research is slowly gathering speed and with its rise, comes the critical need to better understand biodiversity patterns across depths, the connectivity of oceanic regions, and consequently create an  informed, holistic future reef policies and management practices [8, 10].


Bold is Now

Recently, the Philippine Department of National Defense disclosed that Chinese vessels' were spotted in the area, whose unusual movement pattern suggests survey activities rather than merely passing through the region [5].

Aside from this pressing concern, the region is also vulnerable to climate change, urging the Philippine government to assert its rights over the region through biodiversity research, creating a management framework, and consequently declaring Benham Rise as a ‘no-take’ zone [2]. 

We don’t know yet but it might be the last pristine waters we’ll ever lay eyes on. 

Oceana has an online petition urging everyone to declare their support for the protection of Benham Rise. If you are for it, then make your voices heard and put your thoughts into action!


A lone Philippine flag sits in front of a Sarcophyton soft coral at a deepwater reef in Benham Bank(Oceana / UPLB)


Written by:












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[1] Batongbacal, J. L. & Carandang, E. P. (2012). Benham Rise: How the Shelf Was Won.  National Mapping and Information Authority (NAMRIA).
[2] OCEANA (2016). Now is the Time to Protect Benham Rise [Press Release]. Retrieved from http://bit.ly/2o8NDX9 
[3] Perez, A. (2016). Exploring Philippines' Benham Rise Region for Fisheries Development and Management [PowerPoint slides].
[4] Francisco, K. (2017, March 18). Rappler IQ: Fast facts: What you should know about Benham Rise. Rappler. Retrieved from http://bit.ly/2o8Dzxf
[5] Batongbacal, J. (2017, March 14). Opinion: Understanding the issue about Chinese survey vessels in Benham Rise. GMA News Online. Retrieved from http://bit.ly/2nfaoU8
[6] Baker, E. K., Puglise, K. A., & Harris, P. T. (Eds.). (2016). Mesophotic coral ecosystems – A lifeboat for coral reefs? The United Nations Environment Programme and GRID-Arendal, Nairobi and Arendal, 98 p. Retrieved from http://bit.ly/2oemgrf
[7] Kane, C., Kosaki, R. K., & Wagner, D. (2014). High levels of mesophotic reef fish endemism in the Northwestern Hawaiian Islands. Bulletin of Marine Science, 90(2). http://dx.doi.org/10.5343/bms.2013.1053
[8] Bridge, T., Scott, A., & Steinberg, D. (2011). Abundance and diversity of anemonefishes and their host sea anemones at two mesophotic sites on the Great Barrier Reef, Australia. Coral Reefs, 31, 1057-1062. doi: 10.1007/s00338-012-0916-x
[9] Bridge, T. C. L., Fabricius, K. E., Bongaerts, P., Wallace, C. C., Muir, P. R., Done, T. J., & Webster, J. M. (2012). Diversity of Scleractinia and Octocorallia in the mesophotic zone of the Great Barrier Reef, Australia. Coral Reefs, 31, 179-189. doi:10.1007/s00338-011-0828-1
[10] Bridge, T. C. L., Hughes, T. P., Guinotte, J. M., & Bongaerts, P. (2013). Call to protect all coral reefs. Nature Climate Change Volume, 3(6), 528-530. Retrieved from http://bit.ly/2nflb0v





23 March 2017

WEB PAGE UPDATE version 02/2017




Hello to our valuable online users.

http://sealifebase.ca/ is now updated!

Feel free to search for your top most favorite non-fish marine animals.
If you have any comments, corrections, and suggestions, just send us an email.

HAPPY LEARNING!

Through the eyes of a peacock mantis shrimp



Odontodactylus scyllarus (peacock mantis shrimp) is neither a peacock, mantis nor shrimp but a different kind of crustacean which resembles all, regardless of its common name. It is famous for its greatly enlarged hammer-like second raptorial appendage which it uses to smash its prey and defend itself against predators, both in high speeds and with a crushing force [1].

Photo taken in Taiwan by Tim-Yan Chan.

Another great feature of this species is its eyes, which are more advanced than those in humans or in any other species. Its stalked eyes have trinocular vision, depth perception, and can move independently of each other. If humans have 4 different photoreceptors with 3 color channels which allow them to see linearly polarized light, the peacock mantis shrimp has 16 photoreceptors with 12 color channels that allow it to see both linearly and circularly (3D) polarized lights, scientifically called hyperspectral vision [2].

Photo by Steve De Neef.

With this knowledge humans have now developed new ideas that will improve the high-definition capacity of DVDs and CDs by adapting the quarter-wave plates of the mantis shrimp [3].

To know more about the peacock mantis shrimp and other crustaceans, visit SeaLifeBase.

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[1] Patek, S.N., & R.L. Caldwell. 2005. Extreme impact and cavitation forces of a biological hammer: strike forces of the peacock mantis shrimp Odontodactylus scyllarusThe Journal of Experimental Biology 208(Pt 19):3655–3664.
[2] Chiou, T., S. Kleinlogel, T. Cronin, R. Caldwell, B. Loeffler, A. Siddiqi, A. Goldizen, and J. Marshall. 2008. Circular polarization vision in a stomatopod crustacean. Current Biology 18:429-434.
[3] Roberts, N.W., T. Chiou, N.J. Marshall, and T.W. Cronin. 2009. A biological quarter-wave retarder with excellent achromaticity in the visible wavelength region. Nature Photonics 3:641-644.


Written by:

24 February 2017

First record of a potentially invasive mussel Mytella charruana in Manila Bay



Human activities have, in many unprecedented ways, accelerated biological shifts and nuances in our planet. Such is the case for Manila Bay and its inhabitants. A slew of anthropogenic activities such as land and sea-based transportation, sedimentation, fisheries, and reclamation and land conversion has put the ecosystem at high risk for biological invasions.

Meet the Charru mussel Mytella charruana, a newly reported species in Manila Bay, which has been previously documented to be invasive in Florida. A team of researchers led by Dr. Benjamin Vallejo (University of the Philippines Diliman) and SeaLifeBase staff, Jeniffer Conejar-Espedido (University of the Philippines Los Banos) confirms its first recorded presence in the area. Previously identified as Mytilus spp., the bivalve was later identified via DNA barcoding to be Mytella charruana, suggesting its phylogenetic position within the Perna clade. Increasing trend in its abundance from 2014 to 2015 indicates likelihood of establishment and probable competition with the native mussel Perna viridis.  

What makes the species different from Perna and Modiolus is its dark bluish to brown hue and a bluish to purplish nacreous interior. It is also bigger (average of 2.8 cm shell length) compared to another non-indigenous mussel in the area, Mytilopsis, which only grows to 1 cm SL.


Mytella charruana from the Manila Bay PICES
collectors. Photographs by J. Conejar-Espedido.
How did M. charruana reach Manila Bay?

Researchers suggest it is likely to have been introduced via ballast water or through fouled ship hulls. Since mytilids in general adapt and highly reproduce in estuarine and coastal conditions, the persistence of M. charruana is likely.

The spat was first observed at the start of southwest monsoon rainy season. Assuming it has a similar life history profile as that of P. viridis, its introduction must have occurred between late April and early May 2014. This suggests possible competition between the two species. The increasing abundance of M. charruana also indicates its establishment in Manila Bay, but this is yet to be verified in succeeding years. How it could affect the populations of the native P. viridus is, however, is unknown. Further studies on the reproduction, ecology, community dynamics and population genetics are recommended.

Dr. Vallejo’s team also includes, Leanna Manubag, Kevin Carlo Artiaga, Amor Damatac II, Ivan Christian Imperial, Tyrll Adolf Itong, Ian Kendrich Fontanilla and Ernelea Cao.