Demographic trends and reproductive patterns in the northern hairy-nosed wombat (Lasiorhinus krefftii) at Epping Forest National Park (Scientific), central Queensland

The critically endangered northern hairy-nosed wombat (Lasiorhinus krefftii) currently exists at only two locations in Queensland. Management, research and monitoring of the species at the main Epping Forest National Park (Scientific) population has occurred over the last four decades using a variety of tools, with the most complete dataset being provided by burrow activity monitoring over that period. Following a series of trap-based surveys in the 1980s and 1990s, wombat monitoring has employed DNA profiling of hairs collected remotely on sticky tape set at burrow entrances (since 2000), and passive infrared (PIR) cameras (since 2011). These techniques have produced a wealth of new information on the species. Using this new information, we aim to: (1) summarise the available demographic data and present new estimates using novel techniques for L. krefftii at Epping Forest NP; and (2) characterise reproductive patterns and their relationship with environmental factors for L. krefftii at Epping Forest NP. We find an ongoing increase in the population size at Epping Forest National Park, supported by healthy levels of reproduction despite periods of poor environmental conditions, notwithstanding the finding that cumulative monthly rainfall six months prior to sampling influenced birth rates. This trend suggests that the population will likely reach carrying capacity in the near future. It is timely to harvest the population to provide founders to a new site to establish an additional population, which will also reduce the risk of extinction and help secure the future of the species. © 2021 Australian Mammal Society

The short-term effect of radio-packages on a free-ranging large herbivore, the northern hairy-nosed wombat

The short-term effect of radio-packages on the activity of the northern hairy-nosed wombat, Lasiorhinus krefftii, was investigated using activity data-loggers. Adjustment to the radio-package occurred between 10 and 18 days following capture and fitting of the radio-package. Following the adjustment period, activity levels were some 84–97% less than that of the initial activity level after the attachment of the radio-package. We believe that the adjustment period needs to be considered in studies involving the attachment of radio- packages

Field evaluation of supplementary feed and water for the northern hairy-nosed wombat, Lasiorhinus krefftii

The northern hairy-nosed wombat, Lasiorhinus krefftii, is listed as critically endangered in Australia and is restricted to a single population of similar to 90 animals in central Queensland. The area receives low rainfall and is regularly subjected to periods of drought and therefore is at risk from wildfire. There is a clear link between good wet seasons and higher levels of reproductive activity. A long-term management goal of the L. krefftii recovery program has been to determine preferred feed of wombats and to gain acceptance of supplementary feed and water by L. krefftii in order to mitigate the effects of drought and wildfire and potentially increase fecundity and survivorship rates in the population. Prior to this study, there had been several unsuccessful attempts to induce L. krefftii to take supplementary feed and water, but the current study, which was of a longer duration, has shown that L. krefftii will readily take supplementary feed and water. In addition, L. krefftii prefers certain feed types ( Complete-O ( primarily steam-flaked barley with molasses and lucerne and oaten chaff), and Town and Country pellet mix ( primarily wheat, barley and sorghum, with canola and soybean meal)) and will visit sources of feed and water on a nightly basis. Visits by L. krefftii to supplementary feed and water sites were related to the occurrence of rainfall, with visits declining after rain

Demographic monitoring of an entire species (the northern hairy-nosed wombat, Lasiorhinus krefftii) by genetic analysis of non-invasively collected material

Successful management of endangered species may be greatly facilitated by the ability to monitor population trends. The Australian northern hairy-nosed wombat (Lasiorhinus krefftii) is one of the world's most endangered mammals, but precise abundance estimation by trapping surveys has proven exceedingly difficult. A mark-recapture study was conducted in the sole remaining L. krefftii population, based on microsatellite identification of individuals and their gender from DNA in remotely collected single hairs. Population size was estimated to be 113 (95% confidence interval of 96 to 150). This suggests an increase in population size over the previous estimate of 65 (95% CI 42-186) in 1993, although the estimates did not differ significantly. There was a significant male bias in the sex ratio (2.25 males: 1 female), in agreement with recent trapping surveys. The non-invasive approach used here is vital for estimating population size and trends, and hence it is the most important recent advance in the conservation management of the northern hairy-nosed wombat

Reproductive behaviour of the southern-hairy nosed wombat (Lasiorhinus latifrons)

The southern hairy-nosed wombat (Lasiorhinus latifrons) is under threat as its current distribution range and population size is declining. The low reproductive rates observed for this species, both in the wild and within captivity, are a cause for concern; as such this study was designed to provide a comprehensive account of reproductive behaviour in L. latifrons. The behaviour of four groups of captive animals (each 1:2) was remotely monitored for 14 months using a digital video-surveillance system. Using this technology, 13 distinctive reproductive-based behaviours were identified and recorded; each behaviour was allocated to one of two categories: courtship/guarding or mating. The courtship-to-mating ritual was made up of six consecutive phases: investigation, attraction, chase, restraint, coitus and recovery. In total, 423 courtship and 49 mating bouts were observed from five (2:3) wombats. Courtship behaviour was observed on 116 days, with a mean bout number of 3.60.2 per day and a mean total daily time of 29.81.8min. Mating was observed on 24 days, with a mean bout number of 2.10.3 per day and a mean total daily time of 100.19.8min. Courtship occurred over the entire enclosure area and three distinctive courtship locomotor patterns were identified: spiral-circles, straight-lines and random. Matings occurred only in closed spaces and were always accompanied by courtship behaviour. In contrast, only 68% of all courtship days were associated with a mating event. Receptivity in the female wombats lasted for 13h and the behavioural signs of oestrus were so subtle that only the reaction/interest of the male could be used for its detection. The covert reproductive behaviours identified for female L. latifrons closely match those previously reported for captive common wombats and may relate to this species' need to conserve energy

Remote monitoring of the behaviour and activity of captive southern hairy-nosed wombats (Lasiorhinus latifroms)

The nocturnal nature of wombats makes it difficult to learn about their behavioural ecology and activity rhythms in the wild. A facility was established at Rockhampton Zoo to house 12 adult southern hairy-nosed wombats in order to monitor their behaviour by means of video surveillance and provide detailed information on their activity patterns using movement-sensitive radio-transmitters. After one year of monitoring it was established that the wombats spent, on average, as a proportion of total time 69.9% sleeping, 8.8% lying resting, 5.2% feeding, 5.2% exploring, 4.3% performing stereotyped behaviour, 2.5% sitting resting and 4.1% in other activities. Feeding, lying resting and sleeping varied with season by ∼5%. Temporal patterns were bimodal for 8 of the 12 behaviours described, with most 'active' behaviours being expressed between 1800 and 2000hours and 0200 and 0500hours. The activity pattern was characterised by a strong circadian rhythm, with most activity occurring nocturnally. Within active periods there was an alternating rhythm of active and rest periods and activity peaks at the beginning and end of each night. Comprehensive and reliable information on the behavioural ecology, as well as captive management, of southern hairy-nosed wombats was obtained from the remote video and radio-transmitter recordings

The effect of environmental variables on the activity patterns of the southern hairy-nosed wombat (Lasiorhinus latifrons) in captivity: Onset, duration and cessation of activity

The influence of scotoperiod, ambient temperature and humidity on the activity of captive wombats was examined to differentiate environmental influence from that pertaining to food availability. The activity of 12 wombats (Lasiorhinus latifrons) housed at Rockhampton Zoo was remotely monitored by digital video-surveillance for one year, with environmental variables simultaneously recorded via dataloggers. Mean proportion of total daily time spent active was 18.21.8%. Mean daily time spent active varied seasonally according to changes in temperature and humidity. Mean daily activity was greater during winter (30117min) and spring (29516min), than summer (23416min) and autumn (23815min) with differences due to a decrease in the number and length of activity bouts in summer and autumn; presumably these results reflect a need to maintain heat balance associated with exposure to elevated temperatures. Activity was positively correlated with temperature during winter (r≤0.60) and spring (r≤0.52) but negatively correlated during summer (r≤0.58) and autumn (r≤0.49), suggesting the existence of a thermoneutral zone where activity is maximised. We conclude that activity in captive wombats is influenced by environmental variables