Influence of artificial lighting on feeding and movement of the purple sea urchin (Paracentrotus lividus)

master's thesis

• Title (croatian): Utjecaj umjetnog svjetla na hranjenje i kretanje hridinskog ježinca (Paracentrotus lividus)
• Author: Anamarija Šiljeg
• Mentor: Petar Kružić (mentor)
• Committee member: Petar Kružić (predsjednik povjerenstva)
• Committee member: Sven Jelaska (član povjerenstva)
• Committee member: Jasna Lajtner (član povjerenstva)
• Committee member: Ivana Maguire (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2022-02-23, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Light pollution is an emerging anthropogenic stressor for marine ecosystems. About 20% of the
world’s coastlines are affected by artificial light at night - with exposure levels expected to increase
as human populations grow. Despite the omnipresence of artificial light along urbanized
coastlines, a comprehensive understanding of light pollution effects in marine environments is still
lacking. The aim of this study was to investigate the influence of artificial light at night on the
feeding and activity of benthic invertebrate Paracentrotus lividus (Lamarck 1816). The animals
were exposed to a light intensity of 30 lux (first and second experiment) and 60 lux (third
experiment). I conducted three temporally separate experiments which focused on feeding rates
and activity patterns under different lengths of exposure to nighttime lighting. I found that
exposure to artificial light at night does not influence the feeding rate in P. lividus. However, the
light has an effect on the activity pattern. In the presence of artificial light at night, the sea urchin
starts to hide more during the nighttime. Under the predicted increase of artificial light at night
this knowledge is key to understand future changes in benthic communities.

Abstract (english)

Svjetlosno onečišćenje je novi antropogeni stresor za morske ekosustave. Oko 20 % svjetskih
obala noću je pod utjecajem umjetnog svjetla, a očekuje se da će se razina izloženosti povećati
kako ljudska populacija raste. Unatoč sveprisutnosti umjetne svjetlosti duž urbaniziranih obala,
još uvijek nedostaje sveobuhvatno razumijevanje učinaka svjetlosnog onečišćenja u morskim
okolišima. Cilj ovog istraživanja bio je istražiti utjecaj umjetnog svijetla noću na konzumaciju
hrane i aktivnost bentoskog beskralježnjaka Paracentrotus lividus (Lamarck 1816). Jedinke su
bile izložene intenzitetu svjetlosti od 30 luksa (prvi i drugi pokus) i 60 luksa (treći pokus). Provela
sam tri vremenski odvojena pokusa koji su se fokusirali na konzumaciju hrane i aktivnosti pod
različitim duljinama izlaganja noćnom svjetlu. Rezultati su pokazali da izlaganje umjetnom svjetlu
noću P. lividusa ne utječe na količinu konzumirane hrane. Međutim, svjetlost ima utjecaj na
aktivnosti, u prisutnosti umjetnog svjetla noću hidrinski ježinac se počinje više skrivati. Pod
predviđanjima povećanjem umjetnog svjetla noću, ovo znanje je ključno za razumijevanje budućih
promjena u bentoskim zajednicama.

• Keywords: : light pollution; grazing; urbanization; Adriatic sea
• Keywords (english): svjetlosno onečišćenje; strugači; urbanizacija; Jadransko more
• Language: english
• URN:NBN: urn:nbn:hr:217:700521
• Study programme: Title: Ecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra ekologije i zaštite prirode (magistar/magistra ekologije i zaštite prirode)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-03-23 13:12:11