Ecologists from the Faculty of Organic Sciences (SBS) and the Swire Institute of Marine Science (SWIMS) at The College of Hong Kong (HKU) have recognized important ecological dangers related to the discharge of hybrid groupers into Hong Kong’s coastal waters, a apply typically linked to non secular ‘mercy launch’ rituals.
Their examine highlights how the Tiger Grouper-Large Grouper hybrid (TGGG), also called the Sabah grouper, disrupts native marine ecosystems by exploiting distinctive ecological niches and probably changing into a dominant predator. This analysis, the primary to make use of superior DNA metabarcoding to analyse the food plan of this hybrid species, underscores the pressing want for public schooling and conservation measures to mitigate unintended ecological impacts. The findings have been printed within the journal Opinions in Fish Biology and Fisheries.
Hybrid Groupers: A In style Market Species with Hidden Ecological Threats
The TGGG is a hybrid species bred via aquaculture by crossing the Tiger Grouper (Epinephelus fuscoguttatus) with the Large Grouper (Epinephelus lanceolatus). Valued for its giant dimension and fast development, it’s a widespread sight in Hong Kong’s fish markets. Its affordability and spectacular dimension have additionally made it a preferred alternative for native mercy launch practices, the place animals are launched into the wild as an act of non secular benefit. Nonetheless, this seemingly benevolent act has important ecological penalties.
To discover the potential ecological results of releasing hybrid groupers into Hong Kong’s coastal waters, our analysis group utilised DNA metabarcoding to analyse the food plan of TGGG. Turning into the primary to use this methodology to check the dietary habits of this hybrid species, the group extracted and sequenced DNA from the hybrid’s abdomen contents, permitting them to establish its prey, even when the prey was absolutely digested or fragmented. This modern strategy offers an in depth and correct image of the hybrid’s dietary habits and its interactions with native marine ecosystems.
Modern DNA Evaluation Highlights the Menace
The examine discovered that the TGGG is a formidable predator with a particular food plan, feeding on varied prey species not usually consumed by native species — together with fish, crustaceans, and cephalopods. By exploiting broader ecological niches and gaps within the ecosystem the place sources or habitats are underused, the TGGG disrupts native meals webs and is extremely more likely to thrive and set up itself as a dominant predator.
‘Our findings present that the TGGG isn’t just one other launched species, it has the potential to considerably disrupt trophic dynamics and reshape coastal ecosystems,’ stated Professor Celia SCHUNTER of HKU SBS and SWIMS, the examine’s lead investigator.
The researchers warn that the fast development, giant dimension, and absence of pure predators in Hong Kong’s waters make it an exceptionally aggressive species. These traits, mixed with the supply of vacant ecological niches, pose a severe risk to the stability of marine biodiversity in Hong Kong’s coastal ecosystems.
The examine additionally attracts consideration to the position of mercy launch practices in introducing non-native species just like the TGGG into native waters. Dr Arthur CHUNG, the postdoctoral fellow of HKU SBS and SWIMS and co-author of the examine, emphasised the significance of addressing these dangers, ‘This examine underscores the necessity for cautious monitoring and administration to mitigate the unintended impacts of human actions on biodiversity.’
The researchers confused that public schooling and stricter conservation measures are important to minimising the ecological injury brought on by mercy launch and different human actions. These efforts are important for preserving the well being of Hong Kong’s marine ecosystems.
