0000000000482216

AUTHOR

Heikki Hirvonen

0000-0001-8858-0967

Maternal effects in vulnerability to eye-parasites and correlations between behavior and parasitism in juvenile Arctic charr

Hatchery-reared fish show high mortalities after release to the wild environment. Explanations for this include potentially predetermined genetics, behavioral, and physiological acclimation to fish farm environments, and increased vulnerability to predation and parasitism in the wild. We studied vulnerability to Diplostomum spp. parasites (load of eye flukes in the lenses), immune defense (relative spleen size) and antipredator behaviors (approaches toward predator odor, freezing, and swimming activity) in hatchery-reared juvenile Arctic charr (Salvelinus alpinus) using a nested mating design. Fish were exposed to eye-fluke larvae via the incoming water at the hatchery. Fish size was positi…

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Biologian kenttäopetus yliopistoissa: yhteistyöllä uuteen nousuun

Kenttäkurssit ovat keskeinen osa biologian ja lähitieteiden opetusta yliopistoissa. Luonnossa tapahtuva opetus kehittää sekä ymmärrystä tieteenalan teoreettisista perusteista että ammatillisia käytännön taitoja. Kenttäkursseilla omat havainnot muodostuvat oppimisen perustaksi muiden oppimistapojen rinnalla. Vaikka kenttäopetuksen tarpeellisuudesta ollaan yksimielisiä, kenttäkursseja uhkaavat yliopistojen rahoituksen väheneminen ja tutkimusasemaverkoston karsiminen. Tässä kirjoituksessa pohdimme, kuinka uhkista huolimatta kenttäopetuksen määrää, laatua ja kustannustehokkuutta voidaan lisätä yliopistojen ja niiden tutkimusasemien välisellä yhteistyöllä. nonPeerReviewed

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Data from: Maternal effects in vulnerability to eye-parasites and correlations between behaviour and parasitism in juvenile Arctic charr

Hatchery-reared fish show high mortalities after release to the wild environment. Explanations for this include potentially predetermined genetics, behavioural and physiological acclimation to fish farm environments, and increased vulnerability to predation and parasitism in the wild. We studied vulnerability to Diplostomum spp. parasites (load of eye-flukes in the lenses), immune defence (relative spleen size) and anti-predator behaviours (approaches toward predator odour, freezing, and swimming activity) in hatchery-reared juvenile Arctic charr (Salvelinus alpinus) using a nested mating design. Fish were exposed to eye-fluke larvae via the incoming water at the hatchery. Fish size was pos…

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Enhancing salmon conservation releases through improved brain development and behaviour

Captive breeding programmes are based on the practice of taking part of an endangered population to captive environment and releasing the captive-born offspring back to the wild. Despite the vast ecological and economical investment in restoration of endangered animal populations through captive breeding programmes - annually more than 5 billion to salmonid fishes alone - they have been unfortunately unsuccessful. The low success of captive breeding programmes is mainly due to lowered fitness of the released animals and their offspring in the wild. Degradation of many behavioural and other fitness related traits are due to (i) very fast genetic domestication and (ii) habituation to the unna…

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