Evidence map›Paper›PMID 34493065›Full record

ArticleBiology letters2021

Migrating silver eels return from the sea to the river of origin after a false start.

Meelis Tambets, Einar Kärgenberg, Ain Järvalt, Finn Økland, Martin Lykke Kristensen, Anders Koed, Priit Bernotas

Abstract read
In one paragraph

Article in Biology letters, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

3 citing papers in PubMed.

  1. Article
  2. Article
  3. Article
4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

7 authors.

Meelis TambetsWildlife Estonia, Veski 4, Tartu 51005, Estonia.
Einar KärgenbergWildlife Estonia, Veski 4, Tartu 51005, Estonia.ORCID 0000-0003-4391-1368
Ain JärvaltChair of Hydrobiology and Fishery, Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, Tartu 51006, Estonia.
Finn ØklandNorwegian Institute for Nature Research NINA, PO Box 5685, Trondheim No-7485, Norway.
Martin Lykke KristensenTechnical University of Denmark, National Institute for Aquatic Resources, Silkeborg 8600, Denmark.ORCID 0000-0002-2706-0893
Anders KoedTechnical University of Denmark, National Institute for Aquatic Resources, Silkeborg 8600, Denmark.
Priit BernotasEstonian Marine Institute, University of Tartu, Vanemuise 46, Tartu 51014, Estonia.ORCID 0000-0002-1094-6866

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The European eel's singular spawning migration from European waters towards the Sargasso Sea remains elusive, including the early phase of migration at sea. During spawning migration, the movement of freshwater resident eels from river to sea has been thought to be irreversible. We report the first recorded incidents of eels returning to the river of origin after spending up to a year in the marine environment. After migrating to the Baltic Sea, 21% of the silver eels, tagged with acoustic transmitters, returned to the Narva River. Half returned 11-12 months after moving to the sea, with 15 km being the longest upstream movement. The returned eels spent up to 33 days in the river and migrated to the sea again. The fastest specimen migrated to the outlet of the Baltic Sea in 68 days after the second start-roughly 1300 km. The surprising occurrence of returning migrants has implications for sustainable management and protection of this critically endangered species.

Indexed as

AnguillaRiversAcousticsAnimal MigrationAnimalsbehavioural diversityconservation strategyEuropean eelmanagementspawning migrationtelemetry

Identifiers

PMID34493065
PMCPMC8424351

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.