Tropical ecosystem consequences of artificial light at night through moth community changes

Professor Bonebrake, Timothy Carlton   (Principal Investigator (PI))

Professor Michalski Joseph Ryan   (Co-Investigator)

Dr Dingle Caroline Elise   (Co-Investigator)

Professor Ashton Louise Amy   (Co-Investigator)

42

2021-01-01

2025-06-03

996285

Tropical ecosystem consequences of artificial light at night through moth community changes

biodiversity, global change, light pollution, species interactions, tropical insects

EcologyEnvironmental Research

Biology and Medicine (M)

17112620

General Research Fund (GRF)

2020

Completed

1 Characterize spatial variation and temporal change of urbanization and artificial light at night across Hong Kong and over the past two decades. We’ll use remote sensing and available spatial data to quantify these effects to serve as a basis for relating changes in biodiversity and ecosystem change. 2 Using two years of intensive moth trapping surveys (employing both light and fruit-baited trapping methods) across Hong Kong, we’ll determine how moth abundance and diversity changes in response to light, urbanization and both effects combined. This gradient approach will provide a mechanism for untangling the often confounding effects of light and land-use together. 3 Thanks to long-term trapping records of moths in Hong Kong stretching back to the 1990s, we will also examine trends in local species extirpation and colonization and relate these dynamics to levels and changes of light and urbanization. We’ll also examine whether extirpation and colonization are dependent upon moth species traits (e.g. body size, attraction to light, family/taxonomy, or thermal tolerance). 4 We will conduct assays to estimate levels of species interactions/ecosystem processes including herbivory, predation rates of adult and larval moths, abundance of vertebrate predators, and parasitoids. We’ll measure herbivory rates of target leaves over time. For predation of moth adults we’ll video-record orbweaver spider webs overnight and estimate interception of moths. For predation rates moth caterpillars, we’ll deploy plasticine caterpillars in the field and record how many are predated. We’ll survey activity and abundance of bats and birds, common predators of moth adults and larvae. And finally, we’ll collect herbivores from sites and measure rates of parisitoid activity. These assays will be done in coordination with the moth surveys across urbanization and light gradients. 5 Using all of the above, we’ll then be in a position to relate abiotic changes in the environment (light and urbanicity) to changes in moth diversity and abundance and finally changes in trophic dynamics. The study represents a systematic approach to collect data and gain understanding of tropical insect declines and the role of artificial light at night in contributing to such declines.