Habitat suitability and connectivity modeling reveal priority areas for Indiana bat (Myotis sodalis) conservation in a complex habitat mosaic

Context

Conservation for the Indiana bat (Myotis sodalis), a federally endangered species in the United States of America, is typically focused on local maternity sites; however, the species is a regional migrant, interacting with the environment at multiple spatial scales. Hierarchical levels of management may be necessary, but we have limited knowledge of landscape-level ecology, distribution, and connectivity of suitable areas in complex landscapes.

Objectives

We sought to (1) identify factors influencing M. sodalis maternity colony distribution in a mosaic landscape, (2) map suitable maternity habitat, and (3) quantify connectivity importance of patches to direct conservation action.

Methods

Using 3 decades of occurrence data, we tested a priori, hypothesis-driven habitat suitability models. We mapped suitable areas and quantified connectivity importance of habitat patches with probabilistic habitat availability metrics.

Results

Factors improving landscape-scale suitability included limited agriculture, more forest cover, forest edge, proximity to medium-sized water bodies, lower elevations, and limited urban development. Areas closer to hibernacula and rivers were suitable. Binary maps showed that 30% of the study area was suitable for M. sodalis and 29% was important for connectivity. Most suitable patches were important for intra-patch connectivity and far fewer contributed to inter-patch connectivity.

Conclusions

While simple models may be effective for small, homogenous landscapes, complex models are needed to explain habitat suitability in large, mixed landscapes. Suitability modeling identified factors that made sites attractive as maternity areas. Connectivity analysis improved our understanding of important areas for bats and prioritized areas to target for restoration.

     

Using fish models to investigate the links between microbiome and social behaviour: The next step for translational microbiome research?

Recent research has revealed surprisingly important connections between animals’ microbiome and social behaviour. Social interactions can affect the composition and function of the microbiome; conversely, the microbiome affects social communication by influencing the hosts’ central nervous system and peripheral chemical communication. These discoveries set the stage for novel research focusing on the evolution and physiology of animal social behaviour in relation to microbial transmission strategies. Here, we discuss the emerging roles of teleost fish models and their potential for advancing research fields, linked to sociality and microbial regulation. We argue that fish models, such as the zebrafish (Danio rerio, Cyprinidae), sticklebacks (?Gasterosteidae), guppies (Poeciliidae) and cleaner–client dyads (e.g., obligate cleaner fish from the Labridae and Gobiidae families and their visiting clientele), will provide valuable insights into the roles of microbiome in shaping social behaviour and vice versa, while also being of direct relevance to the food and ornamental fish trades. The diversity of fish behaviour warrants more interdisciplinary research, including microbiome studies, which should have a strong ecological (field‐derived) approach, together with laboratory‐based cognitive and neurobiological experimentation. The implications of such integrated approaches may be of translational relevance, opening new avenues for future investigation using fish models.     

Abdominal surgery in foals: a review of 119 cases (1977-1994)

The case records of 119 young horses (all less than age one year) that underwent an exploratory celiotomy during a 17 year period were examined to determine the surgical findings, short- and long-term outcome, and prevalence of small intestinal disease compared to previous reports in the mature horse. Physical and laboratory values were compared for long-term survivors vs. nonsurvivors and the frequency of post operative intra-abdominal adhesions was determined. The most common cause for exploratory celiotomy was small intestinal strangulation, followed by enteritis and uroperitoneum. Six horses died during surgery, 23 were subjected to euthanasia at the time of surgery due to a grave prognosis, and 17 horses died or were destroyed after surgery, prior to discharge from the hospital; the short-term survival was 61%. Nine horses were lost to follow-up. Forty-one horses survived long-term (at least 6 months after surgery), 15 died or were subjected to euthanasia after discharge for reasons related to the prior abdominal surgery, and 8 died or were destroyed after discharge due to unrelated reasons, making the long-term survival 45%. Fifty-three (45%) of the horses presented as neonates, and 66 (55%) presented age 3-12 months. Uroperitoneum and meconium impaction were the most common disease in the neonate. Intussusception and enteritis were the most common diseases in older foals. The overall prevalence of small intestinal disease was 44%. Significant elevations in packed cell volume, heart rate, nucleated cell counts and total protein in abdominal fluid and rectal temperature were observed in nonsurvivors compared to survivors. Nonsurvivors had significantly decreased serum bicarbonate, chloride, sodium, and venous pH values. There was no evidence that location of the lesion affected long-term survival. Horses with a simple obstruction had a higher survival percentage than those with a strangulating obstruction, and horses that underwent an intestinal resection had a lower long-term survival than those horses undergoing only intestinal manipulation. Nineteen (33%) of the foals examined after the original surgery had evidence of intra-abdominal adhesions. Nine of these (16%) had adhesions that caused a clinical problem.     

Ultrastructure of spermiogenesis and spermatozoa of Discocotyle sagittata (Monogenea: Polyopisthocotylea: Discocotylinea).

Ultrastructural analysis revealed that the spermatozoon of Discocotyle sagittata (Leuckart, 1842) is composed of two parallel axonemes, mitochondrion, nucleus and cortical microtubules. The nucleus, which occupies a central/distal position and has an unusual crescent-shaped profile, is slightly shorter than the mitochondrial rod. The two axonemes, which are of unequal length, and the cortical microtubules (up to 68 forming a continuous ring in the principal region) extend almost the entire length of the spermatozoon. A fold of the plasma membrane creates a unilateral flange or undulating membrane. Epifluorescence microscopy indicated that spermatogenesis gives rise to clusters of 64 spermatids connected to a common cytophore. Spermiogenesis and the structure of the filiform sperm of D. sagittata conform to the typical polyopisthocotylean pattern.     

Cajeput oil,an effective botanical against gyrodactylid infection

Infectious diseases are a major welfare issue, economically costly and, from a conservation perspective, threaten susceptible fish populations. Parasite control in aquaculture is over reliant on a limited range of treatments which tend to be low in efficacy, toxic to hosts and have negative consequences on human health and the environment. Here, we tested 22 botanical treatments alongside five controls against Gyrodactylus turnbulli (Harris 1986), in vitro and in vivo, infecting guppies (Poecilia reticulata Peters 1859). Survival of detached parasites was significantly reduced by all treatments with cajuput oil, bay rum oil, bladderwrack, octanoic acid, pine tree oil and barberry killing worms instantly. In vivo, cajuput oil applied with emulsifier was as effective as a licensed livestock dewormer, Levamisole, which is not routinely prescribed for use in fish; hence, cajuput can be considered for further research to replace Levamisole in UK research laboratories as well as in ornamental aquaculture.