Effects of Sex and Breeding Status on Skull Morphology in Cooperatively Breeding Ansell’s Mole-Rats and an Appraisal of Sexual Dimorphism in the Bathyergidae

African mole-rats of the genus Fukomys (Northern common mole-rats) combine a monogamous mating system and pronounced sexual size dimorphism; a pattern highly untypical for mammals. At the same time, they live in cooperatively breeding groups composed of reproductive and non-reproductive members of both sexes. How and to which degree sex and breeding status influence morphofunctional characters in eusocial mole-rats is not well characterized but essential to come to a comprehensive understanding of their peculiar social system. Here, we explore patterns of morphological differentiation in skulls of Ansell’s mole-rats (Fukomys anselli) by means of multivariate analysis of linear skull measurements combined with a 2D shape analysis of cranium and mandible. Compared to females, males display larger skulls relative to body size and show an expansion of the facial portion of the cranium, while reproductive status did not have an effect on any of the traits studied. We also show that species of Fukomys mole-rats display a scaling of relative sexual body size dimorphism in compliance to Rensch’s rule, which is deemed indicative of intense male intrasexual competition. For the bathyergid family as a whole, results of scaling analyses were more ambiguous, but also indicative of Rensch’s rule conformity. In line with genetic field data, our results point to a greater role of male-male conflicts in Fukomys than is traditionally assumed and support the notion that reproductive status does not correlate with morphofunctional segregation in these unusual rodents.

Using camera traps to determine occupancy and breeding in burrowing seabirds

Burrowing seabirds are important in commercial, ecological and conservation terms. Many populations are in flux owing to both negative and positive anthropogenic impacts, but their ecology makes measuring changes difficult. Reliably recording key metrics, the proportion of burrows with breeding pairs, and the success of breeding attempts, requires burrow-level information on occupancy. We investigated the use of camera traps positioned at burrow entrances for determining the number of breeding pairs in a sample to inform population estimates, and for recording breeding success. Linear Discriminant Analyses of time series activity patterns from camera traps successfully partitioned breeding and non-breeding burrows at different stages of the breeding season and had reasonable predictive ability to determine breeding status on a small test dataset. Compared with traditional techniques for determining burrow occupancy (e.g. manual burrow inspection and playback of conspecific calls at burrow entrances), camera traps can reduce uncertainty in estimated breeding success and potentially breeding status of burrows. Significant up-front investment is required in terms of equipment and human resources but for long-term studies camera traps can deliver advantages, particularly when unanticipated novel observations and the potential for calibrating traditional methods with cameras are factored in.

Sex-specific costs of reproduction on survival in a long-lived seabird

Costs of reproduction on survival have captured the attention of researchers since life history theory was formulated. Adults of long-lived species may increase survival by reducing their breeding effort or even skipping reproduction. In this study, we aimed to evaluate the costs of current reproduction on survival and whether skipping reproduction increases adult survival in a long-lived seabird. We used capture–mark–recapture data (1450 encounters) from two populations of Bulwer's petrel ( Bulweria bulwerii ), breeding in the Azores and Canary Islands, North Atlantic Ocean. Using a multi-event model with two different breeding statuses (breeders versus non-breeders), we calculated probabilities of survival and of transitions between breeding statuses, evaluating potential differences between sexes. Females had lower survival probabilities than males, independent of their breeding status. When considering breeding status, breeding females had lower survival probabilities than non-breeding females, suggesting costs of reproduction on survival. Breeding males had higher survival probabilities than non-breeding males, suggesting that males do not incur costs of reproduction on survival and that only the highest quality males have access to breeding. The highest and the lowest probabilities of skipping reproduction were found in breeding males from the Azores and in breeding males from the Canary Islands, respectively. Intermediate values were observed in the females from both populations. This result is probably due to differences in the external factors affecting both populations, essentially predation pressure and competition. The existence of sex-specific costs of reproduction on survival in several populations of this long-lived species may have important implications for species population dynamics.

Native and non-native ornamental aquarium fishes of Bangladesh

The study was conducted in Dhaka, Bangladesh. It was carried out for twelve (12) months from March 2018 to February 2019 to prepare a complete update checklist of native and non-native aquarium fishes of Bangladesh. During the current study, 270 varieties (230 freshwater, 36 marine, and 4 brackish water) belong to 149 species (109 freshwater 73 %, 36 marines 24 %, and 4 brackish water 3 %) of 38 families under 10 orders and 6 crossbreeds’ varieties were recorded. Considering the number of species maximum 83 (55.70 %) was found under the order Perciformes followed by Cypriniformes 24 (16.10 %), Characiformes 18 (12.08 %), Siluriformes 11 (7.38 %), Osteoglossiformes 05 (3.35 %), Atheriniformes 03 (2.01 %), Lepisosteiformes 02 (1.34 %), Polypteriformes 01 (0.6 %), Myliobatiformes 01 (0.67 %) and Cyprinodontiformes 01 (0.67 %). The top five popular species were guppy (13.16 %) followed by goldfish (12.39 %), molly (8.54 %), angelfish (6.23 %), platy (5.93 %). The number of fish species' increasing tendency was 5.96 times in the last 15 years, and 3.31 times in the last ten years. Local farms and aquarists breeders bred 76 varieties under 23 species due to its high demand and profitability. Pricing varied on varieties, species, size, and breeding status (local or abroad), availability, and ranged from BDT 40.00-80,000.00 per pair. According to the findings, aquarium fisheries are highly profitable and will be a potential sector in Bangladesh.