Study

Impacts of bottom trawling on deep-coral ecosystems of seamounts are long-lasting

  • Published source details Althaus F., Williams A., Schlacher T., Kloser R., Green M., Barker B., Bax N., Brodie P. & Hoenlinger-Schlacher M. (2009) Impacts of bottom trawling on deep-coral ecosystems of seamounts are long-lasting. Marine Ecology Progress Series, 397, 279-294.

Actions

This study is summarised as evidence for the following.

Action Category

Designate a Marine Protected Area and prohibit bottom trawling

Action Link
Subtidal Benthic Invertebrate Conservation
  1. Designate a Marine Protected Area and prohibit bottom trawling

    A replicated, site comparison study in 2006 of 25 deep-sea seamounts located south of Tasmania, South Pacific Ocean, Australia (Althaus et al. 2009) found that, four to nine years after prohibiting bottom trawling in marine protected areas, invertebrate community composition was different and abundance lower at protected seamounts compared to trawled and natural (never trawled) seamounts, and diversity and species richness was similar to trawled but lower than at natural seamounts. Community data were reported as graphical analyses and diversity data as diversity indices. Species richness was similar at protected (46 species/1,270 m2) and trawled seamounts (46), but lower than natural seamounts (52). Abundance was lowest at protected (1–3 individuals/m2), compared to trawled seamounts (3–5), and natural seamounts where abundance was the highest (5–18). Species richness, diversity, and abundance were positively related to the cover of habitat-forming corals, which was higher on protected seamounts (3%) than trawled seamounts (0.1%), but lower than on natural seamounts (52%). Invertebrates (including corals) were identified and counted at 25 seamounts from videos transects (up to 4.7 km long, from 1,100 to 1,400 m depth; 38 transects in total). Ten seamounts were located either in continuously trawled areas or in areas where trawling had stopped following establishment of reserves (at some point between 1997 and 2003), and 15 were in never-trawled natural areas. Fishing history of individual seamounts was verified using logbook data from the Australian Fisheries Management Authority.

    (Summarised by: Anaëlle Lemasson)

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