Perspectives on biotic responses to repeated wildfires from decades of long-term empirical studies

ABSTRACT Fire can have marked impacts on biodiversity and on ecosystem condition. However, it is the sequence of multiple fires over a prolonged period of time which can have the most marked effects on biodiversity and on ecosystem condition. A good understanding of these effects comes from long-term studies. In this article we outline some of the key perspectives on the effects of fire on ecosystems and biodiversity from two large-scale, long-term monitoring studies in south-eastern Australia. These are studies in the montane ash forests of the Central Highlands of Victoria and at Booderee National Park in the Jervis Bay Territory. These studies have shown that the effects of fires are strongly influenced by: (1) The condition of an ecosystem before a fire (e.g. the age of a forest at the time it is burnt). (2) Conditions after the fire such as the extent of herbivory in regenerating vegetation and whether the ecosystem is subject to post-fire (salvage) logging. (3) Fire history (e.g. the number of past fires and the time since the previous fire). And, (4) Interactions between fire and other ecosystem drivers such as logging. We discuss some of the key implications for conservation and resource management that arise from these studies including the need to: (a) Reduce the number of stressors in some ecosystems to facilitate post-fire recovery. (b) Recognize that pre-fire human disturbances can elevate fire severity in some forest ecosystems, with corresponding negative effects on elements of the biota, and, (c) Acknowledge the inherent patchiness of wildfires and the value of unburnt areas and places burnt at low severity as critical refugia for some species; it is critical that these locations are managed accordingly (e.g. by limited additional disturbances within them). Finally, many of the insights discussed in this article have emerged only through long-term studies. More long-term monitoring and research is needed to truly understand and better manage fire in Australian ecosystems.

Sound and Camera Recordings of a female Superb Lyrebird (Menura novaehollandiae) and its chick at the nest

ABSTRACT The nest of a Superb Lyrebird, in a spotted gum forest on the south-east coast of Australia, was monitored for approximately 10 weeks. The nest was discovered before the egg was laid, on June 16, 2020. The egg was laid on July 7, and the chick was taken by a Lace Monitor (Varanus varius) on August 29. A camera placed at the nest when discovered was active for the entire monitoring period. Thirteen sound recordings (in 6h periods) were made at the nest between July 16 and August 28 inclusive. The literature on vocalisations by the female lyrebird is scant, and in the light of our data, unrepresentative of her repertoire, especially during her role as parental carer. We present a series of photographs, sonograms and accessible sound recordings. These show specific behaviours of the female as she enters and leaves the nest, and the vocalisations specifically used when the female is approaching or leaving the nest, and when she is interacting with the egg, the chick and an intruder.

Dystocia in a wild Western Tiger Snake (Notechis scutatus occidentalis)

ABSTRACT Dystocia in reptiles is the retention of ova or foetuses within the female due to the failure of the female to complete parturition or oviposition. This disorder is commonly observed in captive reptiles, but has rarely been reported in wild reptiles. We observed a large internal obstruction in an adult female Tiger Snake captured as part of an ongoing population study. We failed to palpate out the object in the field, so we took the snake to a veterinary practice for professional assistance. All non-lethal methods of extracting the object were unsuccessful so we euthanised the specimen and post-mortem dissection revealed five mummified stillborn young lodged in a sealed reproductive tract. Reproductive abnormalities are frequent in Tiger Snakes and large proportions of litters can be comprised of unfertilised eggs, fertilised aborted eggs and stillborn young, yet none of these observations ever resulted in dystocia. It is interesting that this observation occurred in a snake from Herdsman Lake, Western Australia, where the Tiger Snake population is subjected to many anthropogenic stressors. We cannot determine what caused this case of dystocia but suspect it may have been caused by some sort of negative effect onset by the quality of the environment.

Roo the day: evaluating the ShuRoo for prevention of macropod-vehicle collisions

ABSTRACT Collisions between vehicles and macropods pose problems for road safety, animal welfare and wildlife conservation in Australia. We tested the ShuRoo, which is marketed specifically to deter kangaroos from approaching vehicles. We recruited 18 fleet operators with vehicles travelling consistent routes over long distances in rural areas: 59 vehicles fitted with ShuRoos and 40 vehicles without ShuRooss to act as controls. Drivers kept a log of collisions with macropods over an average distance travelled of 46,131 km. The overall mean rate of collisions with macropods was 1.16 per 100,000 km, with no significant difference between vehicles with a ShuRoo (1.32 ± 0.51) versus those without the device (0.68 ± 0.39). Drivers have the capacity to change their behaviour as a coping strategy to the presence of wildlife on the road, but risk a rebound effect if they believe the ShuRoo manufacturer’s claims and do not modify their driving behaviour to match the context. Rather than retro-fitting an ill-conceived device like the ShuRoo, an integrated, inter-disciplinary approach is needed to resolve the pervasive problem of macropod-vehicle collisions.

Vehicle collisions and dog attacks on Victorian koalas as evidenced by a retrospective analysis of sightings and admission records 1997 – 2011

ABSTRACT Koalas moving across open ground risk dog attacks and collisions with vehicles when crossings roads. Historical records from a resident survey, two regional wildlife carers and a state government department wildlife shelter returns database for Victoria, Australia, were examined to determine the importance of certain admission types. Koala Vehicle Collisions (KVCs) and dog attacks were important contributors to the overall intake of injured koalas. However, KVCs were the most numerous recorded cause of koalas entering a wildlife shelter, and the most frequently assigned cause of death. There were relatively high rates of admission into care, and of death, for male koalas. Furthermore, almost twice as many individuals were admitted during the breeding season; sex ratio was not a differentiating characteristic of road-kills between breeding and non-breeding seasons, or by individual months. Comprehensive, accurate and detailed data gathering are essential for effective evaluation of the success of rehabilitation and release, as well as post release survival rates. This, together with population studies would determine whether admission rates reflect the sex ratio of local populations, and whether the high number of injured or killed females has an impact on their viability. Analyses of wildlife carer databases have great potential for decision making in koala conservation.