Catch and release mortality of eel

Project

 (c)

DCF (Data Collection Framework): Mortality of eel released by anglers

European eel (Anguilla anguilla) is an important target species for european anglers. Catch restictions and minimum landing sizes lead to high releases of recreational caught eel.

Background and Objective

The European eel stock has experienced dramatic declines, and is currently considered to be outside safe biological limits and listed as critically endangered by the IUCN. In spite of high release rates, up to now there is no information about the survival rates of released eel caught by anglers. Therefore, a combined field and laboratory study was conducted to

  1. estimate post-release survival of eel for different treatments,
  2. examine factors affecting survival,
  3. investigate the effects of catch-and-release on physical condition, and
  4. study the potential hook shedding mechanism of deeply hooked eels.

Approach

For the field study, a pond was stocked with tagged, wild-caught eels. After four weeks of acclimatization these were captured with rod and line. After release back into the pond eels were held together with control fish for 4 weeks. A comprehensive examination was performed for all eels that had died and survived to determine probable causes of death, progress of wound healing, physical condition, and occurrence of wound infections, haemorrhages and hook shedding. During the supplementary laboratory study, a subsample of deeply hooked eels were held in tanks and frequently radiographed to qualitatively evaluate potential hook shedding.

Thünen-Contact


Involved Thünen-Partners


Involved external Thünen-Partners


Funding Body

  • European Union (EU)
    (international, öffentlich)
  • Bundesland Mecklenburg-Vorpommern
    (national, öffentlich)

Duration

6.2013 - 6.2016

More Information

Projekt type:
Project status: finished

Publications

hits: 2

  1. Weltersbach MS, Ferter K, Sambraus F, Strehlow HV (2016) Hook shedding and post-release fate of deep-hooked European eel. Biol Conserv 199:16-24, DOI:10.1016/j.biocon.2016.04.015
  2. Ferter K, Weltersbach MS, Strehlow HV, Volstad JH, Asos J, Arlinghaus R, Armstrong M, Dorow M, Graaf M de, Hammen T van der, Hyder K, Levrel H, Paulrud A, Radtke K, Rocklin D, Sparrevohn CR, Veiga P (2013) Unexpectedly high catch-and-release rates in European marine recreational fisheries: implications for science and management. ICES J Mar Sci 70(7):1319-1329, doi:10.1093/icesjms/fst104