Threats, risk assessment and recovery action planning for rare and threatened freshwater fish in Queensland’s Wet Tropics region

Abstract

This report presents a comprehensive desktop review, risk assessment and list of potential recovery actions for 22 rare and threatened freshwater fish species in Queensland’s Wet Tropics region. Threats to these species in the Wet Tropics include climate change, land use alteration, invasive species, fire regimes, natural disasters, water resource management and infrastructure, residential development and recreational use, hybridization with sister species, and overharvesting and illicit collection. The risk assessment was conducted during a workshop attended by experts from a range of organisations including government, universities, consultancies and local management.

The risk assessment identified several species at very high risk to some threats. Changes in the flow regime and occurrence of extreme events such as cyclones, drought and landslides were rated as very high risk to Daintree and Cairns rainbowfishes and cling gobies (except Sicyopterus spp.). Remaining populations of Melanotaenia rainbowfishes (Malanda, Utchee Creek and Lake Eacham) are at very high risk of hybridization with eastern rainbowfish, the spread of which is accelerated by habitat degradation that leads to warmer water temperatures. Bloomfield River cod are at very high risk of impacts associated with invasive and translocated fish due to their restricted range and overlapping diet and habitat preferences with introduced species.