AIMS:To determine the major causes of mortality in weka (Gallirallus australis), and to investigate associations between causes of mortality and captivity status, age, sex, decade of submission, and season. METHODS:Necropsy records were obtained from the Massey University School of Veterinary Science/Wildbase Pathology database (Palmerston North, NZ) for weka submitted between 1 January 1995 and 22 March 2022. Causes of mortality were classified into categories based on aetiology. Frequency of diagnosis was tested for association with region of submission, captivity status, age, sex, decade, and season of death. RESULTS:A total of 156 necropsy reports were included in this study, of which 96 (61%) were from wild weka, 57 (36.5%) were captive, and three (1.9%) were of an unspecified captivity status. Weka were submitted from 12 regions across New Zealand. There were 65 (41.7%) adults, 16 (10.3%) juveniles, and 75 (48.1%) weka of an undetermined age among the 156 submissions. Of the weka with a known sex, there was a similar distribution between sexes with 27 (17.3%) males and 29 (18.6%) females. A cause of death was determined in 132/156 (84.6%) cases, with 24/156 (15.4%) cases having an unknown diagnosis. The leading cause of mortality in weka was traumatic injury, which occurred in 65/156 (41.7%), followed by infectious and/or inflammatory diseases in 26/156 (16.7%), and degenerative and/or nutritional conditions affecting 20/156 (12.8%) cases. The distribution of the primary causes of death was found to be dependent on captivity status (p < 0.001). Traumatic and toxic causes of death were more frequent in wild than captive weka. The cause of death was also dependent on season (p < 0.001). There was a significant difference in cause of death between summer and all other seasons (spring p = 0.008; autumn p < 0.001; winter p < 0.001) and between autumn and winter (p = 0.008). CONCLUSION:Trauma was identified as the most significant cause of mortality in the free-living weka necropsied. The inherent and uncertain submissions biases, and low case numbers over a long period of time, means that temporal patterns and the effect of captivity status on causes of mortality should be interpreted with caution.

Case historyTwo clusters of mortality among endangered tuturuatu/tchuriwat'/shore plover (Thinornis novaeseelandiae) have occurred at captive breeding facilities around New Zealand in recent years. In the first, four chicks died at Pukaha National Wildlife Centre (Mount Bruce, NZ) in February 2016, and in the second five adult birds at the Cape Sanctuary (Cape Kidnappers, NZ) died in 2022.Clinical findingsIn 2016, four chicks were noted to become weak, have increased vocalisations and closed eyes prior to death. The remaining chicks were treated for 5 days with amoxycillin/clavulanate orally twice daily. Water containers and brooders were cleaned and disinfected with chlorhexidine. No further mortality was seen.In the 2022 cluster, three adult breeding birds died acutely and five others showed inappetence, weight loss and diarrhoea approximately 10 days after heavy rains flooded the local river. The five birds were treated with amoxycillin/clavulanate orally twice daily and oral fluids for 5 days. Two birds died and three survived. No breeding occurred in the aviaries in the following season.Clinical findingsIn 2016, four chicks were noted to become weak, have increased vocalisations and closed eyes prior to death. The remaining chicks were treated for 5 days with amoxycillin/clavulanate orally twice daily. Water containers and brooders were cleaned and disinfected with chlorhexidine. No further mortality was seen.In the 2022 cluster, three adult breeding birds died acutely and five others showed inappetence, weight loss and diarrhoea approximately 10 days after heavy rains flooded the local river. The five birds were treated with amoxycillin/clavulanate orally twice daily and oral fluids for 5 days. Two birds died and three survived. No breeding occurred in the aviaries in the following season.Pathological findingsIn 2016, the chicks showed pulmonary changes ranging from congestion and oedema to heterophilic inflammation consistent with septicaemia.In 2022, the adult birds showed proliferation of bacteria in the distal small intestine associated with mucosal ulceration and heterophilic infiltration. Acid-fast staining of the caecal contents in one bird showed organisms consistent with Cryptosporidium spp.Pathological findingsIn 2016, the chicks showed pulmonary changes ranging from congestion and oedema to heterophilic inflammation consistent with septicaemia.In 2022, the adult birds showed proliferation of bacteria in the distal small intestine associated with mucosal ulceration and heterophilic infiltration. Acid-fast staining of the caecal contents in one bird showed organisms consistent with Cryptosporidium spp.Laboratory findingsAerobic bacterial cultures of the lung and liver of two affected chicks carried out in 2016 showed heavy growth of Plesiomonas shigelloides. The same organism was cultured from water trays and holding tanks containing water boatmen (Sigara arguta) on which the chicks were fed.In 2022, cultures from the livers of three dead birds each showed a mixed bacterial growth with differing dominant organisms (Aeromonas sobria, Hafnia alvei, Citrobacter freundii and an Enterococcus sp.). PCR and sequencing confirmed Cryptosporidium parvum in the caecum of one bird. Fresh faeces from 24 breeding birds from the captive breeding facilities were negative by PCR for Cryptosporidium spp.The captive breeding facilities obtain water for the aviaries and aquatic invertebrates to feed to the chicks from local freshwater sources. Water quality testing at the Cape Sanctuary revealed concentrations of faecal indicator bacteria in excess of safe drinking water guidelines, with peaks following heavy rainfall.Laboratory findingsAerobic bacterial cultures of the lung and liver of two affected chicks carried out in 2016 showed heavy growth of Plesiomonas shigelloides. The same organism was cultured from water trays and holding tanks containing water boatmen (Sigara arguta) on which the chicks were fed.In 2022, cultures from the livers of three dead birds each showed a mixed bacterial growth with differing dominant organisms (Aeromonas sobria, Hafnia alvei, Citrobacter freundii and an Enterococcus sp.). PCR and sequencing confirmed Cryptosporidium parvum in the caecum of one bird. Fresh faeces from 24 breeding birds from the captive breeding facilities were negative by PCR for Cryptosporidium spp.The captive breeding facilities obtain water for the aviaries and aquatic invertebrates to feed to the chicks from local freshwater sources. Water quality testing at the Cape Sanctuary revealed concentrations of faecal indicator bacteria in excess of safe drinking water guidelines, with peaks following heavy rainfall.Laboratory findingsAerobic bacterial cultures of the lung and liver of two affected chicks carried out in 2016 showed heavy growth of Plesiomonas shigelloides. The same organism was cultured from water trays and holding tanks containing water boatmen (Sigara arguta) on which the chicks were fed.In 2022, cultures from the livers of three dead birds each showed a mixed bacterial growth with differing dominant organisms (Aeromonas sobria, Hafnia alvei, Citrobacter freundii and an Enterococcus sp.). PCR and sequencing confirmed Cryptosporidium parvum in the caecum of one bird. Fresh faeces from 24 breeding birds from the captive breeding facilities were negative by PCR for Cryptosporidium spp.The captive breeding facilities obtain water for the aviaries and aquatic invertebrates to feed to the chicks from local freshwater sources. Water quality testing at the Cape Sanctuary revealed concentrations of faecal indicator bacteria in excess of safe drinking water guidelines, with peaks following heavy rainfall.Clinical relevanceFluctuations in water quality associated with mammalian faecal bacteria can adversely affect bird health and impact on captive rearing of endangered wildlife.

Haematophagous parasites can negatively impact breeding success and their control is often the target of management for threatened bird species. Mitigating parasitism can be difficult and certainly should only be done if parasite control is possible and if successful control improves host species fitness. Here, we use an experiment to test the effect of two alternative chemical methods of Ornithonyssus bursa management in nests of a threatened host species, the New Zealand hihi Notiomystis cincta . We compared a reactive management alternative using Frontline ® (active ingredient fipronil) to control O. bursa infestations after detection to a preventative management alternative using Avian Insect Liquidator (AIL) spray (active ingredients piperonyl butoxide (PBO), permethrin and methoprene) before egg laying. We found that AIL‐treated nests were less likely to be parasitized and parasitism occurred later in nestling development if nests did become parasitized. We also found no difference in egg hatchability nor nestling condition between alternative management approaches but did find nest success was higher in preventative AIL‐treated nests. Our approach highlights the value of an experimental approach in assessing management alternatives in threatened species conservation and the host fitness benefits that can be achieved from control of costly parasitism.

Aims: To characterise and classify wounds in sheep suspected to have been caused by attacks by kea (Nestor notabilis) (kea strike), and to report the prevalence of these wounds on five high country farms in the South Island of New Zealand. Methods: Data were collected from farms between 28 August 2012 and 20 September 2013. Sheep were examined opportunistically immediately after shearing for signs of wounds caused by kea. The age and sex of sheep were also recorded. Wounds were measured and characterised as recent, healing, or healed, and the estimated true prevalence was calculated for each farm. Results: Injuries consistent with kea strike wounds were identified in 70/13,978 (0.5%) sheep examined. The estimated true prevalence varied between farms, from 0 (95% CI = 0-0.16) to 1.25 (95% CI = 0.97-1.61)%. Of the 76 wounds identified, 61 (80%) were located in the lumbar region, and 74 (97%) consisted of full-thickness ulceration of the skin, one showed evidence of injury to muscle and one to bone. The median length of the 63 wounds measured was 6 (min 1, max 23.5) cm, and 10/63 (13%) were categorised as recently healed, 47/63 (62%) as healing, and 17/63 (22%) as recent wounds. Conclusions: The results of this study show that kea strike on sheep was occurring at a low prevalence on the high country farms surveyed. The wounds identified were survivable, but the welfare impact of kea strike on sheep should be considered in balance with the conservation status of kea. There was clear variation in the prevalence of wounds attributed to kea strike between the farms but we were not able to identify the risk factors contributing to these differences. Future studies of kea strike should examine variables such as altitude, local kea density and distribution, and differences in kea strike management and husbandry practices, and should include high country farms without a history of kea strike.

Captive rearing of wild brown kiwi (Apteryx mantelli) is widely carried out to assist in the recovery of this declining species. As a consequence, high densities of immunologically naïve kiwi are commonly housed in semi-captive conditions, with the potential to result in substantial morbidity and mortality from coccidiosis caused by multiple species of Eimeria. Previous research has described circadian variation in oocyst shedding across multiple avian host species. The aim of this research was to describe any circadian variation in oocyst shedding in brown kiwi. Droppings were collected from brown kiwi (n = 4) at a single captive rearing facility using video surveillance to determine the time of excretion, and oocyst counts were undertaken. Results show that two of the Eimeria spp. affecting brown kiwi exhibit a peak in oocyst shedding between 03.00 and 07.00 with few or no oocysts shed between 08.00 and midnight. These results are not able to be explained by the current hypotheses theorising the evolutionary forces behind the development of this adaptive trait. Our findings increase the current understanding of the biology of the Eimeria spp. affecting brown kiwi and have important implications for the management of captive-reared kiwi, in particular for the accurate interpretation of faecal oocyst counts.

AIM: To assess the efficacy of toltrazuril against the Eimeria spp. affecting brown kiwi (Apteryx mantelli). METHODS: Droppings were collected from three brown kiwi, aged <6 months old, at a captive rearing facility in the North Island of New Zealand, between 22 February and 20 April 2017, on 14 sampling dates. Only droppings (n=30) that were excreted between 03:00 and 07:00, as determined using video surveillance, were included for analysis, reflecting the peak time for shedding of coccidial oocysts for brown kiwi. Oocysts were quantified in each sample and Eimeria species identified on the basis of oocyst morphology. All samples were collected between 2 and 10 days after the birds had been treated with 25 mg/kg toltrazuril. RESULTS: Eimeria spp. oocysts were identified in 28/30 individual samples and on 14/14 sampling dates. Oocyst counts varied from 0 to 328,080 oocysts per gram (opg), and at least one oocyst count >10,000 opg was measured on 12/14 sampling dates. Three species of Eimeria were observed, with Eimeria apteryxii and E. kiwii most commonly encountered, whereas only one sample contained E. paraurii. CONCLUSIONS AND CLINICAL RELEVANCE: In the three birds monitored at this research site, there was a high abundance of E. apteryxii and E. kiwii oocysts in droppings despite recent administration of toltrazuril. These results suggest that the populations of Eimeria spp. affecting brown kiwi at this location appear to possess an ability to survive exposure to toltrazuril. Toltrazuril is widely used at captive rearing facilities to limit the effects of coccidiosis in juvenile kiwi. If a lack of efficacy is confirmed, it will be necessary to investigate alternative treatment regimens alongside broader environmental management strategies.

CASE HISTORY: Health monitoring of tuatara (Sphenodon punctatus) at Auckland Zoo between 2001 and 2009 showed that 58/93 tuatara had been affected by dermatitis of unknown origin. From 2011 onwards, cases of suspected fungal dermatitis underwent extensive diagnostic investigations. CLINCAL FINDINGS: Six cases of dermatomycosis were attributed to Paranannizziopsis australasiensis, five in tuatara and one in a coastal bearded dragon (Pogona barbata). Cases presented typically as raised, yellow to brown encrustations on the skin. Severe cases progressed to necrotising ulcerative dermatitis, and in the bearded dragon to fatal systemic mycosis. Following topical and systemic treatments, lesions resolved in all five tuatara. LABORATORY FINDINGS: Histopathological examination of skin biopsy samples revealed dermatitis with intralesional septate branching hyphae. Fungal culture yielded isolates morphologically resembling Chrysosporium species, and isolates were submitted for molecular confirmation and sequencing of DNA. DIAGNOSIS: All six cases were confirmed as dermatitis due to infection with P. australasiensis, on the basis of fungal culture and DNA sequencing of isolates. CLINICAL RELEVANCE: These are the first reported cases of dermatomycosis associated with P. australasiensis infection in tuatara, and the first cases in which systemic therapeutic agents have been used in the treatment of such disease. Tuatara at the Auckland Zoo are now routinely examined every 3 months and tissue samples from any lesions sent for histopathology and fungal culture. Further work to elucidate the epidemiology and significance of P. australasiensis infections in reptiles in New Zealand is important for both welfare and conservation purposes.

The rowi is a critically endangered species of kiwi. Young birds on a crèche island showed loss of feathers from the ventral abdomen and a scurfy dermatitis of the abdominal skin and vent margin. Histology of skin biopsies identified cutaneous larval migrans, which was shown by molecular sequencing to be possibly from a species of Trichostrongylus as a cause of ventral dermatitis and occasional ulcerative vent dermatitis. The predisposing factors that led to this disease are suspected to be the novel exposure of the rowi to parasites from seabirds or marine mammals due to the island crèche and the limited management of roost boxes. This is the first instance of cutaneous larval migrans to be recorded in birds. Severe and fatal complications of the investigation resulted in the death of eight birds of aspergillosis and pulmonary complications associated with the use of bark as a substrate in hospital. Another bird died of renal failure during the period of hospitalisation despite oral and intravenous fluid therapy. The initiating cause of the renal failure was not determined. These complications have the potential to undermine the working relationship between wildlife veterinarians and conservation managers. This case highlights that intensive conservation management can result in increased opportunities for novel routes of cross-species pathogen transmission.

CASE HISTORY:Salmonellosis was suspected as the cause of death in eight wild animals on Tiritiri Matangi Island, in the Hauraki Gulf of New Zealand, between November and September 2011, including three hihi (Notiomystis cincta), a tuatara (Sphenodon punctatus), a masked lapwing (Vanellus miles novaehollandiae), and a saddleback (Philesturnus carunculatus). An outbreak investigation to identify the source and distribution of infection was undertaken over the summer of 2011-2012.CLINICAL AND LABORATORY FINDINGS:Surveillance of five species of forest bird (n=165) in December 2011 returned a single positive result for Salmonella spp. Environmental sampling of 35 key water sources and hihi supplementary feeding stations conducted in December 2011 and March 2012 returned isolates of S. enterica subspecies houtenae and S. enterica serovar Saintpaul from a stream, a dam and a supplementary feeding station. The same serotypes were identified in tissue samples collected from post mortem specimens of the affected birds, and their similarity was confirmed by pulsed-field gel electrophoresis.DIAGNOSIS:Mortality in wildlife associated with infection with S. enterica subspecies houtenae and S. enterica serovar Saintpaul.CLINICAL RELEVANCE:This is the first detection of these Salmonella spp. from wild birds in New Zealand. Our study highlights how active surveillance in response to observed disease emergence (here mortalities) can provide important insight for risk assessment and management within populations of endangered species and inform risk assessment in translocation planning.

AIMS:To identify network measures with relevance to disease spread in a network of movements derived from the Department of Conservation (DOC) translocation records from 1970 to mid-2014, and to identify conservation sites that should be prioritised for surveillance activities and improvements to data collection to make the best use of network analysis techniques in the future.METHODS:Data included the source and destination of translocated specimens, the species and the dates the translocations were expected to occur. The data were used to construct a directed, non-weighted network in which a translocation event represented a tie in the network. Network density, in-degree (movements entering a node of interest) and out-degree (movements leaving a node of interest) and reciprocity were calculated.RESULTS:The data analysed consisted of 692 unique translocations between 307 sites, with the majority (518; 73%) being for birds. The constructed network for bird, reptile and frog translocations comprised 260 nodes, with 34/260 (13%) having two-way movements and 47/260 (18%) non-reciprocal movements. The median degree score (sum of in- and out-degree) was two (min 0, max 36) with a mean of 3.5 in a right skewed distribution. Most sites acted as receivers or senders of consignments with only a few having both high in- and high out-degree, and thus had characteristics that made them sites of interest for surveillance activities. These included the National Wildlife Centre at Mount Bruce, Tiritiri Matangi Island and Te Kakahu (Chalky Island).CONCLUSIONS:The presence of linking sites that join larger clusters within the network creates the potential for rapid disease spread if a pathogen were to be introduced. The important sites that supply or receive specimens for translocations are already well recognised by those performing translocations in New Zealand, and this paper provides further information by quantifying their role within the network.

AIM:To describe a temporal cluster of avian malaria (Plasmodium spp.) at an Operation Nest Egg™ (ONE) site in Rotorua which caused mortality in a juvenile kiwi and had high population prevalence in brown kiwi (Apteryx mantelli).METHODS:A 70-day-old wild-born captive brown kiwi was submitted for post-mortem examination to Massey University Wildlife Health Centre. Post-mortem examination and histopathology were used to determine the cause of death. Plasmodium specific PCR analysis was subsequently conducted on tissue samples and 108 individual blood samples from living kiwi from five ONE breeding sites and two rowi kiwi crèches. Positive PCR products were sequenced to identify the Plasmodium spp. isolated. Where possible, blood smear microscopic examination was used to determine the level of parasitaemia in the infected kiwi.RESULTS:Plasmodium spp. was detected in the kiwi which died and it showed histopathological evidence of disseminated protozoal infection. A high prevalence of Plasmodium was found in blood samples from kiwi concurrently residing at ONE Rotorua by blood smear microscopy (22/32, 68%) and PCR (25/32, 78%). All kiwi with positive blood smears had only a low level of peripheral parasitaemia at the time of sampling. However, 0/17 additional kiwi sampled at Rotorua 3 weeks after the juvenile's death, 0/23 Rotorua juveniles sampled 1 year later and 0/59 kiwi from the five other locations were positive for Plasmodium by these methods. Sequencing analysis revealed a cosmopolitan Plasmodium (Huffia) elongatum lineage in all positive birds.CONCLUSIONS:This is the first description of an avian malaria (Plasmodium spp.) infection associated with mortality and a high population prevalence in brown kiwi at a ONE site in the 20 years of the programme. The study suggests that this level of infection in a population of kiwi was unusual and provides evidence in support of continued vigilance of disease risks associated with this and other conservation management programmes involving wildlife translocation.

This paper describes the effect of a disease outbreak on the success of a translocation for conservation management in a critically endangered species. Three juvenile kakapo from a group of 19 translocated birds died within 72 h of transport between New Zealand offshore islands. Clinical findings, gross necropsy changes, cytology, histopathology and bacterial culture confirmed systemic disease caused by Erysipelothrix rhusiopathiae. On the island from which the kakapo were sourced, positive cultures of E rhusiopathiae were obtained from the medulla of the ulna from 10 out of 15 seabird carcasses examined, suggesting that this could be the source of infection for the kakapo. Immediately after the diagnosis, all of the translocated birds were re-captured and treated with antibiotics. A vaccination programme has commenced using a commercial killed bacterin developed for turkeys. The disease outbreak has had costly implications for the population and conservation management of the species. This is the first report of erysipelas in wild parrots, and the first report of the management of erysipelas in a critically endangered wild population of birds.