Breeding Behavior Research Articles

Reproductive physiology of Indian pangolin (Manis crassicaudata) in Pothwar Plateau, Pakistan

Abstract The Indian pangolin (Manis crassicaudata) is an “endangered” mammal species that is restricted to four range countries of Asia. The ecology and breeding behavior of Indian pangolins is poorly understood due to a lack of scientific data. Due to heavy poaching and illegal killing, the species population has declined drastically in the last decade. Considering the fact that Indian pangolin has low reproductive output, it needs special conservation measures and authentic information about its breeding ecology. We estimated concentrations of three reproductive hormones from scats using ELISA kits in male and female pangolins inhabiting the Pothwar Plateau, Pakistan, to confirm its breeding pattern in its range. Testosterone levels were found elevated from May (0.59 ng/ml) until October (1.28 ng/ml). Oestradiol levels were raised from May (0.59 pg/ml) until December (2.64 pg/ml). Progesterone concentrations were relatively low from January until March but increased from April (4.85 pg/ml) through December (14.0 pg/ml) with highest concentrations (20.13 pg/ml) in September and October. Mean hormone (testosterone, oestradiol and progesterone) concentrations were elevated in winter compared to summer (p < 0.001). The current study is the first one to quantify hormonal levels in this species, and our findings establish the breeding pattern of Indian pangolin.

Male humpback whales switch to singing in the presence of seismic air guns

Ocean noise produced by seismic exploration has been implicated in causing changes in baleen whale hearing, physiology, feeding, breeding, and migratory behaviours. Here, we observed changes in the mating tactics of humpback whales (Megaptera novaeangliae) during a one-hour exposure to nearby seismic air guns. Males employ a conditional mating strategy where they switch between singing and non-singing tactics. Singing is presumably an advertisement signal, while non-singing behaviours include seeking out and joining with females as well as forming competitive groups. During periods of active air guns, the number of male singing whales increased, and singers were more likely to be observed joining females. Conversely, non-singing males were less likely to engage in joining interactions suggesting that active air guns caused a switch in male breeding tactics. Though we cannot translate these effects into changes in breeding success, this indicates that seismic exploration has the potential to alter breeding behaviours in baleen whales.

Behavioral Interactions and Mate Compatibility Influence the Reproductive Success of New England Cottontails (Sylvilagus transitionalis) in a Conservation Breeding Program

Wild populations of New England cottontails (NECs, Sylvilagus transitionalis) are declining and occupy a small proportion of their historic range. To conserve this species, wild-caught cottontails participate in a reintroduction breeding program. To increase the program’s productivity, this study described breeding behavior in pairings with (n = 3 pairings) and without (n = 9 pairings) reproductive success. Females were paired with two males consecutively and behaviors were recorded using 24 h continuous video footage. Activity peaked between 19:00 and 06:00. Copulation was only observed in successful pairings, and the gestation period was 31 days. Successful pairings had a significantly higher rate of follows (p < 0.001) and a lower rate of dashes (p < 0.0001) compared to unsuccessful pairings. Females had significantly higher rates of charge (p < 0.0005), chase (p < 0.0003), and dash (p < 0.0016) than males. Males had higher rates of follow (p < 0.005) than females. Males and females altered their behavior in the presence of different potential mates, suggesting that mate compatibility may influence breeding program productivity. This study significantly expands the understanding of NEC breeding behavior and is applicable to the management of this imperiled species living at low densities in fragmented landscapes.

ESBL-producing Escherichia coli prevalence and sharing across seabirds of central Chile

Antimicrobial resistance (AMR) is a major global public threat, now largely reported in natural environments. Seabirds are carriers of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-E. coli), but different foraging and breeding behaviour could impact ESBL-E. coli circulation. We compared the prevalence and genetic determinants of ESBL-E. coli from resident Kelp gulls (Larus dominicanus, Ld), migratory Franklin's gulls (Larus pipixcan, Lp), and endemic Peruvian pelicans (Pelecanus thagus, Pt) from the Humboldt Current Ecosystem (HCE) of central Chile. From 2020 to 2022, we collected 699 fresh faecal samples (Ld = 449, Lp = 116, Pt = 134), and isolated 271 ESBL-E. coli (39 %). Whole-genome-sequencing (WGS) was performed on 85 E. coli selected isolates to identify their Sequence Type (ST), AMR genes, virulence genes, mobile genetic elements (MGE), and to assess potential interspecies transmission. ESBL-genes were detected in the remaining ESBL-E. coli isolates by PCR. ESBL-E. coli prevalence in Ld (46 % [CI: 42–51 %]) and Pt (34 % [CI: 27–43 %]) was higher than in Lp (15 % [CI: 9–22 %]). WGS revealed 41 ESBL-E. coli STs including pandemic clones ST10, ST58, ST131 and ST410. The blaCTX-M-1 and blaCTX-M-15 genes were the most prevalent among ESBL genes, and were mostly associated with MGE IncI1-I(Alpha) and ISEc9. We also report the pAmpC blaCMY-2 gene associated to MGE Inc1-I(Alpha) and IS640 in two E. coli from a Ld and a Lp. Eight ESBL-E. coli of the same ST were shared by at least two seabird species, including ST10 (Ld and Pt); ST88, ST410 and ST617 (Pt and Lp); ST38, ST58, ST131, and SST1722 (three species). Single nucleotide polymorphism (SNP) phylogenetic analyses of ST38, ST617 and ST1722 showed a low difference of SNPs between STs found in different seabird species, suggesting ESBL-E. coli clonal exchanges. Our results highlight ESBL-E. coli dissemination across seabirds of the HCE, including species that unusually forage on human waste like pelicans.

Phenotypic correlates between clock genes and phenology among populations of Diederik cuckoo, Chrysococcyx caprius.

The Diederik cuckoo, Chrysococcyx caprius, is a small Afrotropical bird in the family Cuculidae. It is taxonomically related to 13 other species within the genus Chrysococcyx and is migratory in sub-Saharan Africa. It has a unique breeding behaviour of being a brood parasite: Breeding pairs lay their eggs in the nests of a host species and hatchlings expel the eggs of the host species. The aim of the present study was to investigate diversity in two circadian clock genes, Clock and Adcyap1, to probe for a relationship between genetic polymorphisms and their role in circannual timing and habitat selection (phenology) in intra-African migrants. DNA extracted from blood was used for the PCR amplification and sequencing of clock genes in 30 Diederik cuckoos. Three alleles were detected for Clock with similar genotypes between individuals from the Northern and Southern breeding ranges while 10 alleles were detected for Adcyap1, having shorter alleles in the North and longer alleles in the South. Population genetic analyses, including allele frequency and zygosity analysis, showed distinctly higher frequencies for the most abundant Clock allele, containing 10 polyglutamine repeats, as well as a high degree of homozygosity. In contrast, all individuals were heterozygous for Adcyap1 and alleles from both regions showed distinct differences in abundance. Comparisons between both clock genes and phenology found several phenotypic correlations. This included evidence of a relationship between the shorter alleles and habitat selection as well as a relationship between longer alleles and timing. In both instances, evidence is provided that these effects may be sex-specific. Given that these genes drive some of the synchronicity between environments and the life cycles of birds, they provide valuable insight into the fitness of species facing global challenges including climate change, urbanisation and expanding agricultural practices.

First Record of Breeding Behavior by the Chestnut-sided Warbler in Washington

The Chestnut-sided Warbler (Setophaga pensylvanica) typically breeds in early successional deciduous forests of the northeastern United States and southeastern Canada. In recent decades, however, the species has become increasingly regular as a vagrant in the western U.S. and Canada. Over several weeks in June and July 2023, near Gig Harbor, Pierce County, we observed the first documented breeding behavior of the Chestnut-sided Warbler in Washington State, including territorial singing by the male and nest-building by the female. The increase in early successional vegetation following logging or wildfires could favor the Chestnut-sided Warbler becoming a regular breeding species in the Pacific Northwest.

Alpine songbirds at higher elevations are only raised with a slight delay and therefore under harsher environmental conditions.

The breeding phenology of birds is often timed to coincide with a peak in food availability. However, the shortening of the vegetation period with increasing elevation may force bird species at high elevations to breed earlier in relation to optimal environmental conditions due to time constraints. We investigated differences in fledging dates in five Alpine woodland songbird species along an elevational gradient from 1500 to 2200 m in Switzerland. We estimated fledging dates from a nationwide citizen science bird monitoring dataset and used the date when the proportion of observations of 'fledged young' reached 50% among all observations indicating breeding behaviour. This measure had the advantage that we could estimate average timing of the broods across a wide geographic range and over many years without the need to search for individual nests. We then compared differences in timing of the broods with climatic conditions and larch budburst across different elevational bands. The daily mean air temperature of 10-15°C was reached 34-38 days later at 2200 m compared to 1500 m, which is a similar delay as found in previous reports on snow melt-out date. The average delay in larch budburst was 19.2 days at 2200 m compared to 1500 m. In comparison, the average timing of the birds' broods was only 5.4 days later in coal tits and 0.5 days later in Alpine tits at 2200 compared to 1500 m (the two species for which we had the narrowest interval estimates). Also, the estimated delay at higher elevations in the broods of song thrushes, mistle thrushes and Eurasian chaffinches was relatively small. Rather than postponing breeding dates to better environmental conditions later in the season that would match the earlier conditions at low elevation, songbirds breeding at higher elevations may thus have evolved adaptations to cope with the harsher conditions.

Can Social Learning Promote Farmers’ Green Breeding Behavior? Regulatory Effect Based on Environmental Regulation

Farmers’ green breeding behavior is significant to environmental protection and sustainable development. Based on the micro-survey data of 1248 beef cattle farmers in Inner Mongolia Autonomous Region and Jilin Province, the OLS model and regulatory effect tests are used to analyze the influence of social learning on farmers’ green breeding behavior and to verify the mechanism of environmental regulation. Key findings include the following: (1) Social learning has a significant positive impact on farmers’ green breeding behavior. (2) Social learning has a significant positive impact on farmers’ willingness to undertake green breeding, farmers’ specific behavior of green breeding, and farmers’ continuous green breeding, among which the effect on specific behavior of green breeding is the most positive. (3) Environmental regulation plays a moderating role in the relationship between social learning and farmers’ green breeding behavior, among which all sub-dimensions of environmental regulation (incentive-based environmental regulation, binding environmental regulation and guided environmental regulation) have positive reinforcing effects, especially the most significant reinforcement effect of binding environmental regulation. Based on the research conclusions, this study proposes policy suggestions such as strengthening the training of farmers, strengthening the learning and communication among farmers’ neighbors, increasing the frequency of farmers’ use of mass media, improving the environmental regulation policy system, and promoting the coordinated development of environmental, economic, and social benefits.

Breeding Behaviour and Management Practices of Struthio camelus under Captive Condition at Private Farm Tehsil Jhando Mari

Breeding Behaviour and Management Practices of Struthio camelus under Captive Condition at Private Farm Tehsil Jhando Mari

K-Mean Based Hyper-Metaheuristic Grey Wolf and Cuckoo Search Optimizers for Automatic MRI Medical Image Clustering

In this paper a new clustering algorithm is proposed for optimal clustering of MRI medical image. In our proposed algorithm, the clustering process implemented by K-means clustering algorithm, due to its simplicity and speed. The optimization process was done by a well-known metaheuristic algorithms Grey Wolf Optimizer (GWO) and Cuckoo Search Optimizer. GWO is a metaheuristic algorithm inspired by the social hierarchy and hunting behavior of grey wolves. It mimics the leadership hierarchy and hunting strategies of wolves to explore the search space efficiently. GWO has shown promising performance in finding high-quality solutions compared to other well-established optimizers. It explores the solution space to find better cluster assignments that minimize the overall intra-cluster variance. By leveraging the exploration potential of GWO, the proposed algorithm aims to improve the quality of the clustering results. Furthermore, the Cuckoo Search Optimizer (CS) is combined with GWO to enhance the algorithm's ability to find a global solution. Cuckoo Search is a metaheuristic algorithm inspired by the breeding behavior of cuckoo birds. It employs random search and Levy flights to diversify the search process and avoid getting trapped in local optima. By combining CS with GWO, the proposed algorithm aims to increase the likelihood of finding the optimal clustering solution.

Large dinosaur egg accumulations and their significance for understanding nesting behaviour

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct species. However, existing methods often rely on the presence of complete eggs and embryo remains, and sedimentological criteria that are only applicable to well-structured sediments. In this study, we introduce an innovative approach to characterize egg accumulations in structureless sediments, where traditional nest structures may not be preserved. Our methodology employs a unique combination of sedimentological, taphonomic, geochemical, and geophysical proxies for the study of egg accumulations. We applied this approach to the egg accumulation from Paimogo (Jurassic, Portugal), traditionally interpreted as a nest. Our findings reveal that the Paimogo egg assemblage is a secondary deposit, resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph clutches. The eggshell vapor conductance results, coupled with sedimentological evidence, suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season, likely during the dry season to prevent the embryos from drowning. This research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless sediments. Our findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms, contributing to our understanding of dinosaur ecology.

A Conspectus of the 74 Taxa of Cotoneaster Ehrhart Ex Medic. (Rosaceae) in India

Available evidence from cytology [X=17 2n=34 (3 ssp.). 2n=51 (3 spp.) and 2n=68 (14 spp.)] judged against the breeding behaviour of the parental species and their F1 hybrids. All suggest that Cotoneaster Ehrhart ex Medic. must be treated as a largely apomictic genus, in which recognition of 'micro-species', sensu Klotz (1957-Seq. 1978), is justified. The distributional data of the 74 taxa indigenous to India brings up 25 species as endemic (asterisked) to the Indian Sector of the Himalayas and one, viz., C. buxifolia Wall. ex. Lindl., to the Nilgiri ill ranges. A conspectus of the 74 species, arranged alphabatically with correct nomenclature typification, relevant synonyms and their occurrence in different Sectors/Zones of India is appended.

A Scoping Review on the Epidemiology of Orthobunyaviruses of Canadian Public and Animal Health Relevance in the Context of Vector Species.

Background: Mosquito-borne orthobunyaviruses are a growing priority for public and animal health in Canada. It is anticipated that disease incidence will increase due to a warming climate, given that habitats are expanding for reservoir hosts and vectors, particularly in Canada. Little is known about the ecology of primary vectors that perpetuate these orthobunyaviruses, including the viral transmission cycle and the impact of climatic and landscape factors. Methods: A scoping review was conducted to describe the current state of knowledge on the epidemiology of orthobunyaviruses relevant to Canada. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews guidelines was used to characterize studies focused on vector species. A literature search was conducted in six databases and gray literature. Eligible studies characterized orthobunyavirus epidemiology related to vector species, including viral competency, geospatial distributions, seasonal trends, and/or risk factors. Results: A total of 1734 unique citations were identified. Screening of these citations revealed 172 relevant studies, from which 87 studies presented primary data related to vectors. The orthobunyaviruses included Cache Valley virus (CVV), Jamestown Canyon virus (JCV), Snowshoe Hare virus (SHV), and La Crosse virus (LACV). Surveillance was the predominant study focus, with most citations representing the United States, specifically, LACV surveillance in Tennessee, followed by CVV and JCV in Connecticut. Orthobunyaviruses were detected in many mosquito species across multiple genera, with high vector specificity only being reported for LACV, which included Aedes triseriatus, Aedes albopictus, and Aedes japonicus. Peridomestic areas were positively associated with infected mosquitoes compared with dense forests. Orthobunyavirus infections, coinfections, and gut microbiota affected mosquito feeding and breeding behavior. Conclusion: Knowledge gaps included Canadian surveillance data, disease modeling, and risk projections. Further research in these areas, especially accounting for climate change, is needed to guide health policy for prevention of orthobunyaviral disease.

E-Commerce Participation, Subjective Norms and Grassland Utilization Pressure: An Empirical Evidence of Herdsmen in Inner Mongolia, China

The general requirements of China’s rural revitalization strategy are industrial prosperity, ecological livability and rich life. However, the traditional livestock breeding model has struggled to balance the dual requirements of production development and ecological protection, and it is urgent to inject new impetus and explore new development paths. At present, e-commerce has become a bridge between pastoral areas and cities, herdsmen and consumers. E-commerce participation is not only an important starting point for herdsmen to increase the added value and profit space of livestock products, but also an effective way to change the original breeding behavior based on the premise of destroying grassland. Therefore, this paper presents an in-depth study on the issue of e-commerce enabling grassland ecological restoration, aiming to provide more scientific and effective guidance for e-commerce to be used to achieve a win–win situation in economy and ecology. Therefore, based on the data of 271 herdsmen in pastoral areas of Inner Mongolia, we used the OLS model and the two-stage least squares (2SLS) method to identify the direct impact of herdsmen’s e-commerce participation on grassland utilization pressure. The empirical results show that e-commerce participation can significantly decrease the grassland utilization pressure. The conclusion was still valid after alleviating endogeneity and conducting a robustness test. The results of a mechanism analysis suggest that the reduction effect of e-commerce participation on grassland utilization pressure is mainly due to price incentive, reputation incentive and place identity. Subjective norms can strengthen the inhibitory effect of e-commerce participation on grassland utilization pressure. Furthermore, a heterogeneity analysis demonstrates that e-commerce participation has a better, decreased impact on the grassland utilization pressure on the banners of China’s rural e-commerce demonstration county program. Under a counterfactual assumption, if herdsmen who can participate in e-commerce choose not to do this, their grassland utilization pressure will increase.

First description of the breeding biology and behaviour of the near threatened northern sooty woodpecker <i>Mulleripicus funebris</i> (Valenciennes 1826) (Piciformes: Picidae) in Luzon Island, Philippines

Although generally regarded as keystone species within forest communities, woodpeckers (Picidae) remain understudied in the Philippines. We describe for the first time the breeding biology and behaviour of the IUCN Near Threatened northern sooty woodpecker Mulleripicus funebris based on observations from a single active nest found in a standing dead Parkia timoriana tree at the Subic Watershed Forest Reserve, Zambales, Luzon, Philippines. The nest was observed from late February to May 2022 for a total of 63.7 hours. The cavity was 16.4 m from the ground and had opening dimensions (L x W) of 9.0 x 8.0 cm and a depth of 37.0 cm. Breeding of M. funebris lasted ≈76-83 days from nest excavation (≈27 days) to fledging. The brood size was two. Both parents were involved in nest building and chick-rearing activities. The male M. funebris contributed more hours during nest building and diurnal incubation whereas the female dominated feeding of nestlings and nest sanitation during the time of fledging. We recommend the retention of standing dead trees as nesting sites for woodpeckers and already existing holes for other cavity-nesting fauna.

Automatic Identification of Pangolin Behavior Using Deep Learning Based on Temporal Relative Attention Mechanism.

With declining populations in the wild, captive rescue and breeding have become one of the most important ways to protect pangolins from extinction. At present, the success rate of artificial breeding is low, due to the insufficient understanding of the breeding behavior characteristics of pangolins. The automatic recognition method based on machine vision not only monitors for 24 h but also reduces the stress response of pangolins. This paper aimed to establish a temporal relation and attention mechanism network (Pangolin breeding attention and transfer network, PBATn) to monitor and recognize pangolin behaviors, including breeding and daily behavior. There were 11,476 videos including breeding behavior and daily behavior that were divided into training, validation, and test sets. For the training set and validation set, the PBATn network model had an accuracy of 98.95% and 96.11%, and a loss function value of 0.1531 and 0.1852. The model is suitable for a 2.40 m × 2.20 m (length × width) pangolin cage area, with a nest box measuring 40 cm × 30 cm × 30 cm (length × width × height) positioned either on the left or right side inside the cage. A spherical night-vision monitoring camera was installed on the cage wall at a height of 2.50 m above the ground. For the test set, the mean Average Precision (mAP), average accuracy, average recall, average specificity, and average F1 score were found to be higher than SlowFast, X3D, TANet, TSN, etc., with values of 97.50%, 99.17%, 97.55%, 99.53%, and 97.48%, respectively. The recognition accuracies of PBATn were 94.00% and 98.50% for the chasing and mounting breeding behaviors, respectively. The results showed that PBATn outperformed the baseline methods in all aspects. This study shows that the deep learning system can accurately observe pangolin breeding behavior and it will be useful for analyzing the behavior of these animals.

Breeding behavior analysis in a large captive colony of African penguins (Spheniscus demersus) and its implications for population management and conservation

The African penguin Spheniscus demersus, frequently housed in zoos, holds potential for future reintroduction efforts due to its declining wild population. This paper aims to explore various aspects of reproductive performance in African penguins within a large ex situ colony at Zoo Wrocław in Poland, covering 9 years of breeding behaviors. The analysis reveals parallels in colony growth and partner change patterns with those observed in the wild. Positive correlations were found between breeding success and pair-bond duration, with the increasing colony size influencing reproductive performance. Contrary to their wild counterparts, captive African penguins initiate breeding attempt and produce a fertilized egg at a younger age. However, successful breeding still requires gaining experience or forming pairs with more experienced partners. Our research indicates that providing captive African penguins with unlimited food resources and sufficient nesting space results in rapid colony growth. The increased colony size facilitates breeding behaviors that positively influence population dynamics, particularly through the maintenance of long-term pair bond relationships and the potential for partner changes when necessary or desirable to enhance breeding success. We present compelling case studies in pair fidelity, offering valuable insights and implications for the management of captive populations and conservation efforts.

Breeding behavior and parental care in the wild Oriental stork, Ciconia boyciana, reintroduced in Japan

Breeding behavior and parental care in the wild Oriental stork, Ciconia boyciana, reintroduced in Japan

Roosting and Breeding Ecology of Birds in Shola Sky Island Forests: A Systematic Review and Analysis

The Shola Sky Island forests, located in the Western Ghats of India, are unique ecosystems renowned for their high elevation, isolated patches of evergreen forests, and rich avian biodiversity. Understanding the roosting and breeding ecology of birds in these forests is essential for their conservation and management. However, a comprehensive synthesis of the existing literature on this topic is lacking. This systematic review aims to fill this knowledge gap by analyzing and summarizing the available research on the roosting and breeding ecology of birds in the Shola Sky Island forests. The review focuses on various aspects of bird ecology, including roosting site selection, roosting strategies, breeding phenology, nest site selection, nesting behaviors, and factors influencing non-roosting and breeding behaviors. The literature search encompasses studies conducted in the Shola Sky Island forests, covering a wide range of bird species and their ecological requirements. Findings from the review highlight the importance of specific habitat characteristics, such as vegetation structure, microclimate, and resource availability, in influencing bird roosting and breeding behaviors. The availability of suitable roosting sites and nesting habitats within the forest plays a crucial role in determining the distribution and abundance of bird species. Factors such as food availability, altitudinal movements, social interactions, and territoriality also impact non-roosting and breeding behaviors in these forests. Furthermore, the review emphasizes the challenges posed by habitat fragmentation, climate change, and human activities to the roosting and breeding ecology of birds in the Shola Sky Island forests. Understanding these threats and their implications for bird populations is essential for effective conservation and management strategies.

Species- and sex-specific chemical composition from an internal gland-like tissue of an African frog family.

Intraspecific chemical communication in frogs is understudied and the few published cases are limited to externally visible and male-specific breeding glands. Frogs of the family Odontobatrachidae, a West African endemic complex of five morphologically cryptic species, have large, fatty gland-like strands along their lower mandible. We investigated the general anatomy of this gland-like strand and analysed its chemical composition. We found the strand to be present in males and females of all species. The strand varies in markedness, with well-developed strands usually found in reproductively active individuals. The strands are situated under particularly thin skin sections, the vocal sac in male frogs and a respective area in females. Gas-chromatography/mass spectrometry and multivariate analysis revealed that the strands contain sex- and species-specific chemical profiles, which are consistent across geographically distant populations. The profiles varied between reproductive and non-reproductive individuals. These results indicate that the mandibular strands in the Odontobatrachidae comprise a so far overlooked structure (potentially a gland) that most likely plays a role in the mating and/or breeding behaviour of the five Odontobatrachus species. Our results highlight the relevance of multimodal signalling in anurans, and indicate that chemical communication in frogs may not be restricted to sexually dimorphic, apparent skin glands.