Kate J. Brandis

Assessing nesting metrics in large waterbird breeding rookeries is challenging due to their size and accessibility. Drones offer a promising solution, but their comparability with ground surveys remains debated. In our study, we directly compared ground and drone data collected simultaneously over the same breeding areas. Drones excel in accessing remote terrain, enhancing coverage, mapping colony extent and reducing sampling bias. However, flying at the low altitudes required to capture young chicks in nests within densely populated rookeries poses challenges, often requiring observer presence and diminishing the distance advantage. Drones enable rapid data collection and facilitate accurate ibis chick counts, particularly at the “runner” stage when chicks are very mobile, and our surveys found significant differences in the counts between drone and ground surveys at this nesting stage. Ground surveys, on the other hand, provide valuable contextual observations, including water variables and sensory cues concerning the health of the colony. Both methods offer unique insights, with drones providing high-resolution aerial data and ground surveys complementing with human observations. Integrating both methods is ideal for comprehensive waterbird monitoring and conservation.

Almost half of Australian freshwater turtle species are formally listed as threatened, but little is known about the effects of water management and other factors on the abundance and health of freshwater turtles in arid and semi‐arid regions. This study investigated how river flows (including the controlled release of water from an upstream storage facility, or ‘environmental flow’) and water quality might affect the abundance and nutritional status of three freshwater turtle species in three dryland rivers of the Murray–Darling basin in south‐eastern Australia. No response in abundance or nutritional status of the broad‐shelled turtle, Chelodina expansa , the eastern long‐necked turtle, Chelodina longicollis , and the Macquarie turtle, Emydura macquarii , was detected in relation to river flows, possibly because of the small magnitude of the environmental flow. However, for C. expansa , the catch per unit effort (CPUE) was negatively related to increasing macrophyte cover, electrical conductivity (EC, an indicator of salinity), and turbidity. CPUE for C. longicollis was positively related to macrophyte cover and EC, and for E. macquarii it was positively related to macrophyte cover. Haematological measurements suggested that the turtles had healthy nutritional status. Body condition and blood glucose and protein were related significantly to EC, whereas haematological measurements varied significantly among species and between spring and summer. The main conclusion is that water management measures to help the conservation of these turtles should include sufficient environmental flow to produce overbank flooding, thereby creating and maintaining a wide range of habitat suitable for the differing needs of the individual species.