J. Zool. Bot. Gard., Volume 4, Issue 4 (December 2023) – 11 articles

A population of burrowing owls (Athene cunicularia) under professional care at Zoomarine Portugal presented with sudden respiratory clinical signs. Clinical management included a thorough diagnosis plan, including in-house fecal analysis that revealed the presence of ovoid unioperculate eggs. In the postmortem examination of one hyperacute dyspneic specimen, adult nematode parasites were collected and identified based on their morphology as Cyathostoma (Hovorkonema) americana. Even after a broad-spectrum deworming protocol as part of the treatment and metaphylaxis approach, the incidence of parasitic reinfection was high. The complete clinical resolution was only accomplished after the identification and management of the possible focus of infection, a wild population of cattle egrets (Bubulcus ibis) that frequently congregated above the owls’ habitat. To the authors’ best knowledge, this is the first report of infection by Cyathostoma (Hovorkonema) americana in burrowing owls. Although nematodes of the family Syngamidae are not commonly included in the differential diagnosis of infectious respiratory agents of birds of the order Strigiformes, this report highlights the possibility of opportunistic parasitism in a zoological context, especially where there is a continued proximity to free-ranging avifauna. Full article

Many progressive aquariums worldwide house various elasmobranch species as part of their commitment to conservation awareness and the long-term well-being of these creatures. These aquariums face the challenge of enabling these natural predators to live harmoniously with other fish without triggering natural predation. This research, conducted at Zoomarine Algarve in Southern Portugal, aimed to investigate the behaviour of three elasmobranch species (Carcharhinus melanopterus (1:1:0), Triaenodon obesus (1:0:0), and Pteroplatytrygon violacea (0:3:0)) when exposed to different feeding mechanisms. The goal was to provide them with opportunities for alternative predatory behaviours beyond their typical feeding techniques and to reduce the likelihood of natural predation. The study took place under controlled conditions within a community habitat. Four feeding methods (pole, short buoy, long buoy, and PVC) were tested during morning, afternoon, and evening periods, using five different prey species. The results shed light on which feeding method aligns best with each species’ distinct physiological standards and predatory tendencies and revealed their prey preferences. All three species interacted with all feeding methods, with P. violacea showing a strong preference for the pole method. T. obesus favoured bony fish, while C. melanopterus showed a preference for cephalopods. P. violacea interacted with all prey types but displayed no marked preference. These various feeding methods and prey options also function as environmental enrichment strategies, enhancing the complexity of the habitat and providing the animals with more choices and control, ultimately promoting their welfare in captivity. Full article

The combination of animals and plants in zoological gardens provides the opportunity for conservation within the grounds. An example is pollination gardens that support free-moving butterflies and bees. Pollination gardens and other areas with plants also support a wide range of other non-captive animals, including soil-associated invertebrates. This study targeted land snails, a species-rich group that links the brown decomposition food web and the plant-based web that is preyed upon by fireflies and birds, among others. A survey of 24 sites within the Oklahoma City Zoo and Botanical Garden revealed a diverse snail fauna of 23 species. The majority were native species but included 10 non-native species that are common regional urban species, likely introduced through the plant trade. No distributional pattern of snails was evident, probably because of the similar management scheme throughout the zoo. Snails and other observed soil-associated invertebrates (e.g., isopods, millipedes, and earthworms) support non-captive birds and other animals. Lightly managed areas with leaf litter and downed wood are especially conducive to snails and other soil-associated invertebrates and are nesting sites for bees. These communities can form conservation demonstration areas that can be the basis of educational programs, including outreach programs. Full article

Zoos represent a social construct, whose form is influenced by societal development. During the 20th and at the beginning of the 21st century, they have been transformed from assembled collections to internationally managed insurance (ex situ) populations, and these transformations required some changes in taxa numbers and composition. Previous studies have already identified the trend of reducing the number of taxa kept in zoos worldwide. The aim of the present study is to verify this trend in Europe in more detail and therefore to identify the changes in taxa richness and mammalian taxa richness from 1959 to 2016 in the same set of 67 European zoos while considering their opening period (before 1900 and 1900–1960) and location with respect to the former Iron Curtain (Eastern vs. Western Bloc). There was no significant decrease in taxa richness; on the contrary, there was a significant increase in taxa richness for the former Eastern Bloc zoos. There was a significant decrease in mammalian taxa richness for zoos opened before 1900 and those of the former Western Bloc. These results demonstrate that mammalian taxa have declined in numbers to some extent and that the decline mostly concerns older zoos and those that have historically reached a different stage of development. This suggests that European zoos have not been subject to trends uniformly and should apply different and appropriate strategies when facing future (not only conservation) challenges. Full article

In 2008, Steinhart Aquarium at the California Academy of Sciences in San Francisco, CA, USA, unveiled a brand new facility with the 212,000 gallon Philippine Coral Reef habitat as its iconic centerpiece. Designing and managing a system that consists of a living reef this large, with associated invertebrates and teleosts, has been a challenge for the aquarium’s husbandry and veterinary teams. Establishing appropriate lighting, water quality, and flow has required a scientific approach and resulting adjustments to the original habitat design. The medical management of reef species has required an in-habitat approach as well as trial-and-error therapeutics. Determining the criteria for assessing the welfare of corals and other tank inhabitants has been a shifting process that has heavily utilized photography-tracked changes and other quantitative parameters as baselines. This report details the successes and limitations of establishing the environmental and veterinary management of this mesocosm. The consideration of interplay between species is discussed, and recommendations for monitoring welfare both on an individual and tank level are made. Making adjustments for the benefit of the exhibit and its animals is key for the unique aquarium displays that comprise captive coral reef systems. Full article

The aim of this study was to document a case of parasite co-infection in a captive Bactrian camel and to supply morphometric data of the found pathogens. It concerned a 20-year-old male animal inhabiting Sofia Zoo, Bulgaria. A decreased appetite and gastrointestinal disorders were observed in it during the summer of 2022. Improvement in the animal’s condition was achieved after the administration of antibiotics, sulfonamides, and other symptomatic medicines. However, two weeks after treatment, clinical symptoms reappeared. Then, a diarrheal fecal sample from the animal was subjected to parasitological examination by direct smear and flotation and sedimentation techniques. Multiple infections by helminths (Trichostrongylus sp., Haemonchus sp., Oesophagostomum sp., Trichuris sp., and Dicrocoelium sp.), ciliates (Buxtonella cameli), and protozoa (Eimeria cameli) were found, with E. cameli being reported for the first time in zoo conditions. Deworming led to the recovery of the general condition and appearance of the animal’s feces, but two weeks later, it died suddenly. We considered that the parasitic infection was not the direct cause of the fatal outcome, and its presence, other health disorders, and the advanced age of the animal were among the contributing factors. This case reveals the need to combine planned preventive deworming with routine parasitological diagnostics to take timely and targeted actions to protect the health of animals inhabiting zoo facilities. Full article

Emotions in animals may be expressed by arousal and understanding this often relies upon the monitoring of their behaviour. Under human care, animals’ arousal states may be linked to husbandry decisions, whereby animals may display arousal responses to scheduled events such as feeding and human interaction. Here, we investigate vocal correlates of arousal associated with public presentations of bottlenose dolphins (Tursiops spp.) in human care by comparing vocal production rates and characteristics between high and low arousal contexts. Elevated arousal during the day compared with overnight was characterised by increased signature and non-signature whistle production. High intensity broadband crack vocalisations were produced less than whistles during the day and did not correlate with increased arousal around presentation times. Three of ten dolphins increased signature whistle production before and/or after presentation sessions, indicating elevated arousal and variation in individual responses. Many individuals elevated minimum frequency and suppressed maximum frequency of signature whistles in a way that correlated with higher arousal contexts, indicating that these may therefore be good indicators of changes in arousal state. Overall, our study demonstrates that passive acoustic monitoring can provide a useful indication of arousal linked to husbandry decisions, and that individual variation in vocal responses, likely linked to personality, is important to consider. Full article

A bibliometric analysis of 349 scholarly documents published on the topic plant nativity and endemism from 1991–2022 was carried out using the ‘bibliometrix’ tool, developed through the R programming language. The results revealed a significant increase in the number of publications on plant nativity and endemism research since 1991. Of the total of 349 documents that were analyzed, 38 are single authored documents, and the average number of documents per author is 0.278. Each document has received an average of 33.67 citations, with 3.18 citations per year per document. The relationship between the number of authors and the number of articles that they have published follows a power-law distribution. Based on Bradford’s law, only eight were found to be the core sources. Mexico, followed by the USA, has produced the highest number of documents on plant nativity and endemism. The present study suggests that it is necessary to categorize data on endemism by floristic provinces, not by political subdivisions. Synecological studies are also needed, since endemic plants exist within communities. Models that accurately predict levels of endemism on the basis of easily measurable environmental variables should be useful for the rapid identification of endemic-rich areas. Recognition of the importance of plant endemism and the implementation of conservation measures is crucial for preserving biodiversity hotspots. Both in situ and ex situ conservation efforts are essential for protecting endemic species and preventing their extinction. By integrating these approaches, we can contribute to the long-term conservation and management of endemic plant species. Full article

The Fisher principle states that species should produce offspring at a ratio of 1:1 unless there are sex-specific differences in rearing costs. Research conducted across taxa has found that animals will vary the sex ratio of their offspring so as to maximize personal fitness in response to various ecological and biological variables. This phenomenon has been especially well studied within the Avian class. Professionally managed populations provide a useful framework within which to study the impacts of numerous variables on sex allocation strategies. Zoological facilities may be especially motivated to investigate this phenomenon due to corresponding conservation and welfare implications. We analyzed a large dataset containing the demographic data of over 1 million zoo-housed birds for species-specific offspring sex ratio biases. The offspring sex ratios of 19,867 zoo-hatched dams were calculated, and the median offspring sex ratio of 277 species from 25 orders was calculated across two 20-year time periods. We used a Wilcoxon signed rank tests with a Holm Bonferroni alpha criterion in order to determine if species medians differed from parity. Only one species in one time period displayed a significant species median offspring sex ratio. The limits of our dataset are discussed. We propose that future research should further explore the determinants of sex allocation strategies for species held within zoological facilities. Full article

Many wild otariids (sea lions and fur seals) strand along the California coast annually with seizures following presumed exposure to harmful algal blooms (HABs). This is a long-term case study of a stranded subadult male Guadalupe fur seal (Arctocephalus townsendi) that stranded in 2001 and within days after admission began demonstrating seizure activity. The epilepsy was stabilized with antiepileptic drug (AED) therapy and advanced imaging was performed. Magnetic resonance (MR) scans showed signs of encephalopathy consistent with domoic acid (DA) toxicosis. This fur seal was deemed “non-releasable” and over the following 19 years, he received supportive veterinary care and AED treatment at a permitted facility. In the summer of 2020, the fur seal showed progressive behavioral and functional deterioration whereupon humane euthanasia was performed. Post-mortem MR and diffusion tensor images (DTI) were acquired. A volumetric comparison with historic scans showed evidence of severe progressive unilateral right hippocampal atrophy. Histopathology confirmed severe chronic right and mild left hippocampal atrophy. The progressive degenerative brain changes demonstrate how adaptive brain function can be with neuronal atrophy secondary to DA exposure. This case highlights some considerations and decision-making processes needed for the rehabilitation and placement of wild stranded otariids with acquired epilepsy secondary to DA toxicity. Full article

Zoological institutions, which were once exclusively for entertainment, are now leaders of wildlife conservation. This centuries-long transition was punctuated by key milestones that reformed wild animal exploitation into a mission of protection. Modern zoos perform ex situ activities to preserve natural resources, which are enabled by the housing of wild species. Zoo-managed animals facilitate new scientific knowledge, public education, and strategic breeding to maintain genetic diversity. Prioritizing animal welfare management is a key advancement for modern zoos, as it lessens stress and improves quality of life. Environments enriched with sensory stimuli promote naturalistic behaviors and provide opportunities for instinctual activities like foraging and hunting. This increases resiliency by reducing stress and boredom. However, such approaches only benefit welfare when appropriately matched to the animal. Behavioral responses to environmental cues reflect how animals experience their environment, and properly documenting them informs management decisions. Other modern advancements include enclosure designs, research initiatives, public education programs, species-specific staff training, and collaborative population management among zoos. This review chronicles the milestones that shaped the role of modern zoological institutions in species and habitat preservation. It also discusses opportunities for the continued evolution of welfare management practices, which is fundamental information for zoo employees and stakeholders. Full article