A comparative study of the species composition of discards from five fisheries from the Algarve (southern Portugal)

  • Published source details Erzini K., Costa M.E., Bentes L. & Borges T.C. (2002) A comparative study of the species composition of discards from five fisheries from the Algarve (southern Portugal). Fisheries Management and Ecology, 9, 31-40.


This study is summarised as evidence for the following.

Action Category

Use an alternative commercial fishing method

Action Link
Marine Fish Conservation
  1. Use an alternative commercial fishing method

    A replicated, randomized controlled study in 1996–1997 of an area of pelagic water in the Atlantic Ocean, off Portugal (Erzini et al. 2002) reported that pelagic purse seine nets appeared to discard fewer species of cartilaginous fish (Chondrichthyes) such as sharks and rays, and bony fish (Osteichthyes) compared to other types of fishing gear. Data were not tested for statistical significance. For shark/ray species, of which 85% were usually discarded, 1 species was caught in pelagic purse seines, 2 in demersal purse seines, 7 in trammel nets, 10 in fish trawls and 13 in crustacean trawls. For bony fish, of which 34% were usually discarded and 54% frequently discarded, 34 species were caught in pelagic purse seines, 55 in both demersal purse seines and crustacean trawls, 49 in trammel nets and 66 in fish trawls. In March 1996 to June 1997, a total of 57 fishing trips on 24 vessels were sampled at random by fisheries observers in Algarve waters. Overall, data were collected from 18 pelagic purse seine sets, 33 demersal purse seine sets, 11 trammel net sets, 30 crustacean trawl tows and 36 fish trawl deployments. All fish were identified and counted. Fished depths were 30–500 m, depending on gear type. Due to the variety of vessels and gears sampled, specific gear details were not given in the original paper.

    (Summarised by: Chris Barrett)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust