Untangling the human-jellyfish connection

Last month's mini-symposium Q-quatics 2019: Road Ahead has been productive, providing a means for Q-quatics to communicate possibilities to execute its fisheries and oceans mandate through collaborations with the global scientific community.

Many participants took an interest in the talk of Lucas Brotz, jellyfish expert and Q-Quatics Cnidaria Scientist, as he shared the ever growing, inevitable relationship of humans and jellyfish today.

Based on a rigorous study Brotz led, jellyfish populations, indeed, have been increasing since 1950: out of the 45 large marine ecosystems (LMEs) analyzed, 62% showed increasing trends [1]. This brought with it changes that we are only now seeing—more reports of children dying from box jellyfish stings [4], swarms of jellyfish regularly interrupting fishing activities [2], jellyfish responsible for massive power failure in Luzon [3], and jellyfish turning into snacks [4]. While the demand for jellyfish for food has increased, huge economic losses are incurred by many related industries [4].

Fig. 1. Map of population trends of native and invasive species of jellyfish by large marine ecosystem (LME) (Source: Brotz et al. 2012)

A regular day for fishermen in Japan, clearing the infestations of Nomura (Copyright: Shin-ichi Uye, Hiroshima University)

Counter-measures to control jellyfish populations have been done but with mixed results. A more apparent move, to exploit jellyfish as food, was seen as an opportunity to deter this global rise. However, as Brotz pointed out, eating our way out isn't the likely solution. Rather, adaptation may be our best approach [4]. 

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Sources:
[1] Brotz, L., Cheung, W. W., Kleisner, K., Pakhomov, E., & Pauly, D. (2012). Increasing jellyfish populations: trends in large marine ecosystems. In Jellyfish Blooms IV (pp. 3-20). Springer, Dordrecht. Retrieved from https://bit.ly/2Ea4tvi

[2] Vince, G. (2012, April 5). Jellyfish blooms creating oceans of slime. BBC. Retrieved from https://bbc.in/2hLG1Cc

[3] BBC (1999, December 11). Jellyfish blamed for Philippines blackout. BBC News.  Retrieved from https://bbc.in/2LHCIv2

[4] Brotz, L. (2019, January 31). Jellyfish and humans - the big picture. Q-quatics 2019: road ahead symposium. 

Q-quatics holds a mini-symposium

Q-quatics launches its year with a mini-symposium held at IRRI Training Center in Los Baños, Laguna last January 31. Local and international marine scientists shared emerging issues on fisheries: from (1) small-scale fisheries academy in Senegal, to (2) global assessment of exploited marine fisheries, to (3) a new analysis of global freshwater finfisheries, to (4) ballast water management, to (5) jellyfish-human relationship, to (6) the use of global databases as identification tools, and (7) the FAO global record of stocks and fisheries. If you're keen to know more about the symposium, you may read Mundus maris piece here. 

Participants, both local and international—UPLB, UP Diliman, BFAR-NFRDI, NAST, National Museum, Haribon Foundation, RARE, ASEAN Center for Biodiversity, Amanpulo Resort, Oceana Philippines, Wetlands International and IRRI—contributed to a lively and productive discussion.

Cornelia E. Nauen, Q-Quatics Board of Trustee

Speakers: Top left to right: Dr. Maria Lourdes Palomares, Dr. Peter Sorensen, Dr. Benjamin Vallejo Jr.;
Bottom left to right:  Dr. Lucas Brotz, Mr. Rodolfo Reyes Jr. and Dr. Nicolas Bailly

This event became an avenue to conceive possible projects, form partnerships and strengthen existing ones with different organizations. These possibilities include the next steps inherent to the declaration of ASEAN being a "safe risk area" for international shipping, call for increased awareness in the importance of freshwater fisheries, conducting jellyfish population studies in the Philippines, and developing machine learning tools for fish identification.

Deception in the distant seas

The adage Honesty is the best policy applies to almost everything, including fisheries sciences. Apparently, more than 90% of the marine catches in the African waters by China's "giant" fishing fleet is not officially reported to UN's Food and Agriculture Organization (FAO).

Pew Ocean Science Division of The Pew Charitable Trusts.

This supposed gross misrepresentation of numbers, not only by China but by many countries as well, greatly impacts the creation of management plans that bases its data from FAO. Clearly, using wrongful statistics results to ineffective management plans which can lead to further depletion (and eventually extinction) of fisheries stocks.

Mega trawlers in West African waters. Source

For more details, click here or read the full paper here.

More sharks and manta rays in the CITES Appendices, please!

From the name itself, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) aims to ensure that the international trade of wild animals and plants will not cause their extinction. Only a handful out of the thousands of listed species in the CITES Appendices are marine species, and despite all efforts to include more, most proposals were rejected.

According to the Review of the State of World Marine Fisheries Resources published in 2005 by the Food and Agriculture Organization of the United Nations (FAO), more than 50% of marine fish stocks are fully exploited, 17% are overexploited and 7% are already depleted. The statistics are highly alarming and require immediate action.

As of this writing, the Sixteenth meeting of the Conference of the Parties (CoP16) is happening in Bangkok, Thailand. Today they will vote on the addition of five shark species and all manta rays to Appendix II. This newly published paper* from the Fish and Fisheries was written primarily to help the CoP in their discussions by providing information that can help address their concerns.

Hoping that they vote in favor of the sharks and manta rays!

* Executive summary can be found here (also available in French and Spanish).

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 UPDATE (as of 15 March 2013): All proposals were approved! More details here.

Spot shrimp (Pandalus platyceros)

The spot prawn or spot shrimp, Pandalus platyceros, is also known as the California spot prawn and as the Alaskan prawn, names which tell us that the spot shrimp is found along the Pacific coast of North America, that is, from Alaska to San Diego, California (Cowles, 2005); but, they are also found in the Sea of Japan to the Korea Strait (Department of Fisheries and Oceans, 1999).

As its name implies, this red shrimp has distinct white spots, which are found on the first and fifth segments on both sides of its back (Cowles, 2005). The name Pandalus has an obscure origin, but it may be related to the Old Sussex word, pandle, meaning 'shrimp', which is believed to have its origin from the Low Latin, 'pandalus' (Sussex Archaeological Society, 1859), which might be related to the Latin 'pandus', i.e., crook-backed (Hopper). The name 'platyceros' is of Latin meaning 'broad-horn' (Hopper).

Pandalus platyceros photo from Monterey Bay Aquarium

Spot shrimp belongs to Pandalidae family, which is protandrically hermaphroditic, that is, it initially develops and functions as a male and transforms into a female on the third or fourth year and remains as female onwards (Barr, 1973).  Male becomes sexually mature at a total length of 15 cm (Butler, 2011).  It uses Agarum fimbriatum and Agarum cribrosum kelp beds as nursery habitats (Marliave & Roth, 1995) 

They are nocturnal and epibenthic and are found in bed rocks to muddy sand substrates with adequate shelter for day light hiding. They are carnivorous and feed by scavenging dead animal materials and preying on amphipods, euphausids, limpets annelids and other shrimps (Barr, 1973)

They are popular seafood and the subject of an important fishery in British Columbia (Department of Fisheries and Oceans, 1999).



Written by:

Fishing Down the Marine Food Web

A visual presentation  by Hans Hillewaert, 
as inspired by the work of Daniel Pauly.

The phrase "fishing down the food web" has been very popular in the fisheries industry since the late 1990's, but it is definitely far from being a cliché.

Introduced in this article by Pauly et al. (1998), this phrase simply mean that over time, traditional fisheries has exploited the stocks of large predatory fishes and has now moved on to smaller species, oftentimes farther or deeper in the ocean (sometimes both).

Pauly believes that with this continuing decline, it won't be long before people would start having jellyfish sandwiches. Yikes! Can you imagine yourself having jellyfish meals?

To learn more about this concept, visit www.fishingdown.org. It is recently launched by the Sea Around Us Project to present case studies from around the world that have largely been ignored in the objections to fishing down, and present a brief response to these objections which are largely based on misunderstandings and allegations.

Happy learning!

Written by:

Lealde Pacres-Urriquia

Research Assistant

The SeaLifeBase Project

New publication in PLOS ONE

SeaLifeBase Project Principal Investigator Daniel Pauly and SeaLifeBase Project Coordinator Maria Lourdes Palomares are co-authors in a new publication entitled "Gaining Perspective on What We’ve Lost: The Reliability of Encoded Anecdotes in Historical Ecology", published in the peer-reviewed open-access journal PLOS ONE.

Abstract:

Historical data are essential in fisheries management and conservation, especially for species that suffered significant population declines prior to ecological data collection. Within the field of historical marine ecology, studies have relied on anecdotal evidence, such as written accounts by explorers and interviews of different generations of resource users, to demonstrate the former abundance of certain species and the extent of their ranges. Yet, do we all agree on how these anecdotes are interpreted? This study examines the way that different people interpret anecdotes extracted from historical narratives. We outsource a survey to 50 randomly selected people using Amazon Mechanical Turk (www.mturk.com) and ask them to ‘code’ historical anecdotes based on their perceived abundance of species. We perform intercoder reliability tests to show that people's perceptions of historical anecdotes are generally consistent. The results speak to the reliability of using people's perceptions to acquire quantitative data, and provide novel insights into the use of anecdotal evidence to inform historical ecology.

Read and/or download the rest of the paper here.

Posted by:

Lealde Pacres-Urriquia

Research Assistant

The SeaLifeBase Project