Artificial light at night and warming impact grazing rates and gonad index of the sea urchin Centrostephanus rodgersii

Artificial light at night (ALAN) is a growing threat to coastal habitats, and is likely to exacerbate the impacts of other stressors. Kelp forests are dominant habitats on temperate reefs but are declining due to ocean warming and overgrazing. We tested the independent and interactive effects of ALAN (dark vs ALAN) and warming (ambient vs warm) on grazing rates and gonad index of the sea urchin Centrostephanus rodgersii. Within these treatments, urchins were fed either ‘fresh’ kelp or ‘treated’ kelp. Treated kelp (Ecklonia radiata) was exposed to the same light and temperature combinations as urchins. We assessed photosynthetic yield, carbon and nitrogen content and C:N ratio of treated kelp to help identify potential drivers behind any effects on urchins. Grazing increased with warming and ALAN for urchins fed fresh kelp, and increased with warming for urchins fed treated kelp. Gonad index was higher in ALAN/ambient and dark/warm treatments compared to dark/ambient treatments for urchi..., Refer to the manuscript for more information. , , # Data from: Artificial light at night and warming impact grazing rates and gonad index of the sea urchin Centrostephanus rodgersii

This README file was generated on 13-03-24 by Amelia Caley

This project is for the manuscript \"Artificial light at night and warming impact grazing rates and gonad index of the sea urchin Centrostephanus rodgersii\" from an experiment conducted in June - August 2022 in Sydney, Australia, testing the combined effects of Artificial Light at Night (ALAN, 50 lux) and warming (+ 2 degrees C) on urchin grazing rates and gonad index, kelp photosynthetic yield and C and N content, and on trophic interactions between urchins and kelp. The file called \"Urchins ALAN Final\" is the original dataset created during the experiment. This file can be imported for use with the original code, or the cleaned, long format dataset (created within this code) can be used. Photosynthetic yield, urchin gonad index and urchin grazing rates are visualised and modelled in the Urchin AL...