Occurrence Of Breeding Research Articles

Twenty-four-year investigation of the reproductive biology of Glis glis in England (Rodentia: Gliridae)

Nest boxes were used to monitor a population of edible dormice (Glis glis) for 24 years. Details were recorded of reproductive condition, age and co-habitation by ca. 10,000 tagged individuals. Age at first breeding, periodic failure to breed, ‘absenteeism’ among adults, changing litter size with growth of young, survival rates and lifetime reproductive output were documented. The proportion of communal breeders and their kinship was examined as well as the occurrence of breeding by subadults. Life strategy and potential benefits of seasonal and annual behaviour are discussed.

Local prior information and mainland overflow explain avian colonisation in a major land‐bridge island

AbstractAimThe relative roles of intrinsic and extrinsic factors, and those of local and regional variables, in island colonisation, remain major biogeographical questions. Thus, we analysed avian colonisation records of a large land‐bridge island, defining successful colonisation as the occurrence of breeding during at least 3 consecutive years, at species level with the aim of identifying the main determinants of island colonisation by birds.LocationMallorca (Balearic Islands, western Mediterranean).Major TaxaAll avian species recorded in Mallorca Island.MethodsWe performed logistic regression by fitting generalised linear mixed models to data. We explored seven explanatory variables and performed model selection based on Akaike's information criterion.ResultsA total of 26 bird species colonised the island during the study period, a rate of ca. 0.7 colonising species/year. Only seven species were found to attempt colonisation unsuccessfully. Bird species with the highest colonisation probabilities were those with growing population trends on the mainland and a previous status as wintering species on the island (0.58), followed by wintering species with a stable population trend on the mainland (0.37).Main ConclusionsThe high rate of colonisation indicates that the process of incorporation of new species has been very dynamic. Colonisation was dependent on a local factor (having prior information about the island) and a regional factor (density dependence on the nearby continent). However, it was not influenced by body size, diet, habitat or IUCN level of threat. Based on the results of our modelling, we present a predictive list of likely future colonisers.

Breeding phenology of amphibians in a Mediterranean ephemeral stream (Ardèche, France)

We present the results of the monitoring of breeding phenology of an assemblage of eight species of amphibians in a Mediterranean ephemeral stream, located in the Ardèche department, France. For most species, during 11 consecutive years, phenology was rather constant from year to year, which is rather unusual in Mediterranean temporary ponds. The occurrence of summer breeding was not rare for three species: Pelobates cultripes (Cuvier, 1829), Pelodytes punctatus (Daudin, 1803) and Hyla meridionalis Böttger, 1874. Breeding occurrence is linked to rewetting events caused by active karst resurgences, fuelled by periods of intense rainfall episodes called “cévenol” episodes. We document for the first time a triannual breeding occurrence (spring, summer, and autumn), and an in situ record of a short tadpole development period, concerning particularly P. cultripes. The ecological factors which can explain this species richness and these unusual observations are outlined. In conclusion, we encourage the conservation and monitoring of amphibian communities in ephemeral streams, as the natural and scientific interests for this type of habitat are often underestimated.

Human-controlled reproductive experience may contribute to incestuous behavior observed in reintroduced semi-feral stallions (Equuscaballus)

Equine reproductive behavior is affected by many factors, some remaining poorly understood. This study tested the hypothesis that a period of captivity during the juvenile period and human-controlled reproduction may potentially be involved in the disruption of the development of incestuous mating avoidance behavior in sanctuary-reintroduced male Konik polski horses. Between 1986 and 2000, cases of incestuous behavior in harem stallions born and reared until weaning in the sanctuary were studied. Eight males lived in the sanctuary's feral herd for the rest of their lives (the non-captive group; nC). They gained their own harem of mares without human intervention (no human-controlled reproductive activity, nHC). Another five stallions were removed as weanlings, reared in captivity and then reintroduced as adults (captive, C). Three of these C stallions were used as in-hand breeding stallions, one as a “teaser” (human-controlled reproductive activity, HC) and one was not used for reproduction in captivity (nHC). Reproductive records for 46 mares, daughters of all 13 harem stallions, were scrutinized and cases of incestuous breeding were recorded by interrogation of foal parentage records. C stallions failed to expel more daughters than nC stallions (33% vs. 18%, P = 0.045), and mated with significantly more of them (28% vs. 11%, P = 0.025). Interestingly, HC stallions expelled fewer (60%) and successfully mated with more (33%) daughters that nHC stallions (84% expelled, P = 0.013, and 10% successful mating with daughters, P = 0.010). All HC stallions bred incestuously at least once.We propose that human intervention during a critical period of development of social and reproductive behavior in young stallions, by enforced separation from their natal herd and in-hand breeding, may contribute to their later aberrant behavior and disruption of inbreeding avoidance mechanisms in these stallions. The previous occurrence of human-controlled breeding may be one of the factors promoting incestuous behavior of stallions in natural conditions. The uninterrupted presence of stallions in their harems and herd member recognition may also play important roles in inbreeding avoidance in horses.

Occurrence of repeat breeding in crossbred dairy cattle

The present research work was undertaken to evaluate the occurrence of repeat breeding (RB) among crossbred dairy cattle for three years from January 2017 to December 2019. Crossbred cows having apparently normal genitalia and showing regular oestrous cycle but failing to conceive even after three consecutive inseminations were selected as RB cows based on data collected from breeding registers. The occurrence of RB in the year 2017, 2018 and 2019 were 29.20, 24.12 and 19.52 per cent, respectively with an overall occurrence of 23.60 per cent. Detailed clinico-gynaecological and ultrasonographic examinations of 41 RB cows were carried out for the identification of various etiological factors during the study period (September 2019 to August 2020). Samples for endometrial cytology were collected during oestrus by cytobrush technique to rule out cytological endometritis (sub clinical endometritis). The occurrence of various identified causes of RB were cytological endometritis (17.07 %), fibrosis of cervix (7.31 %), endometritis (7.31 %), follicular cyst (4.88 %), kinked cervix (2.44 %), uterine unicornis (2.44 %) and other reasons (58.54 %). Repeat breeding is a major cause of infertility in crossbred dairy cattle and early diagnosis is essential for the effective management and to enhance production.

Phenology of Antler Casting and Occurance of Late-Breeding in Nebraska White-Tailed Deer

White-tailed deer (Odocoileus virginianus) in Nebraska primarily breed in November (stimulated by photoperiod), but this season extends into December and January for unfertilized females and healthy fawns reaching the appropriate breeding weight by winter. Variation in the typical mating period can be attributed to geographic region, skewed sex ratios, and fawns reaching sexual maturity during their first year of birth. During April of 2019, we observed late season breeding by a male white-tailed deer in the central Platte River valley and documented late antler casting for this same late-copulating male. An additional male was observed in April of 2020 still retaining antlers within the region. To understand the irregularity of these observations relative to the central Platte River valley, we documented observations of early and late antler casting utilizing long-term cast antler collection and camera trap data. We were able to establish a baseline for antler casting phenology within this region to denote a shift in average casting timeframe (more than one month later than previously recorded in this region) and document early and the latest known antler casting within the literature. Herein, we detail the variation in antler casting phenology for white-tailed deer in this region, and the latest known occurrence of natural breeding in the state. Our findings help us better understand the life history of the Nebraska white-tailed deer population and can assist state wildlife biologists and property managers as they assess seasonal harvest regulations and adaptively manage the changing resource.

Evaluation of seasonal breeding of the domestic canary (Serinus canaria) in an artificial environment

ABSTRACT: The domestic canary (Serinus canaria) has been bred for hundreds of years to improve the quality of its plumage and its song. Reproduction in this species occurs seasonally, stimulated by a gradual increase in day length. Although, the occurrence of seasonal breeding in canaries is well known, whether canary reproduction can be manipulated remains unknown. Our objective was to determine whether the conditions of captivity (photoperiod and temperature) can be adjusted to enable canaries to reproduce outside of their natural breeding season. Thirty days before the natural breeding season, canary pairs were assigned and separated into three different groups: External Control (housed outdoors under ambient conditions), Artificial Control (housed artificially indoors under conditions similar to the external conditions), and Artificial Altered (housed artificially indoors for five months, with the photoperiod gradually manipulated to simulate that of the natural breeding season) groups. The number of clutches laid was greater in the Artificial Control than in External Control; however, more birds hatched in the External Control. In the Artificial Altered group, the beginning of the breeding season was delayed when the same parameters were used. Although, further research is needed, this study presents new data to assist in the development of protocols that entail gradual changes in environmental conditions to try to reduce the impacts of the processes on animal welfare.

Occurrence and risk factors of repeat breeding on household dairy cows of Hathazari in Chattogram

Repeat breeding is one of the important problems in dairy sector of Bangladesh causing economic loss due to reduced production and additional cost on management of cows. This study was conducted to estimate the occurrences of repeat breeder and its frequency distribution in household dairy cows. Total 120 cows from 15 selected households in Hathazari Upazilla, Chattogram during January to March 2018 were considered for this study. Repeat breeding defined as cows less than 10 years old failure to conceive after 3 or more regularly successive services (AI/Natural) in the absence of detectable abnormalities. Households were selected with the history of cow(s) failure to concept even after three or more regular services without any detectable abnormality. Cow’s level factors, households level factors and few organisms in uterine environment were studied as risk factors on repeat breeding.The results revealed25 % (N=120) repeat breeder cows in the household dairy. Cows level factors find out that aged with >6-8 years (33%) and having uterine infection (52%) had significantly influenced the occurrence of repeat breeding. In regards of household level factors, minimum level of farmer’s education, poor drainage system and dirty cows were influenced (P≤0.05) repeat breeding cows. Uterine fluid bacteriological culture showed that Staphylococcus spp. (76%) and E. coli (13%) were commonly found in repeat breeder cows.

Alternative Life-History in Native Trout (Salmo spp.) Suppresses the Invasive Effect of Alien Trout Strains Introduced Into Streams in the Western Part of the Balkans

Diversity of native trout fish Salmo spp. comprises a variety of nominal taxa in Serbia, Montenegro and Bosnia and Herzegovina. Recent mapping of the resident trout detected brown trout S. trutta (sensu stricto) of the Atlantic (AT) mtDNA lineage introduced into populations of both tentative Danubian trout S. labrax and of tentative Adriatic trout S. farioides belonging to the Danubian (DA) and Adriatic (AD) mtDNA lineages, respectively. In addition, an introduction of the tentative Macedonian trout S. macedonicus of the AD lineage was detected in the one native population of the tentative S. labrax. In almost all recipient non-migratory trout populations, a cross breeding between the native and introduced trout was detected by heterozygosity in either only LDH-C nuclear locus, or in LDH-C and particular microsatellites’ loci. Exception is one population where both resident and migratory, lake-dwelling individuals of the tentative Adriatic trout spawned at the downstream section of a stream in Montenegro, none of microsatellites’ alleles of Atlantic brown trout that were introduced into the upstream section was detected. The occurrence of cross breeding between Adriatic and brown trout was evident in the upstream, isolated section. It seems that migrating, lake-dwelling Adriatic trout in combination with their resident, stream-dwelling conspecifics suppress introgression of genes from those situated upstream, strongly introgressed by brown trout. Having this in sight, it is noteworthy to warn on the occurrence of the migratory brown trout in the Danube River at the broader Iron Gate Gorge area. They were recorded to migrate in late summer and early fall from the Iron Gate One reservoir to the lower sections of tributaries devoid of any trout fish. However, some of those streams home very special native trout of the DA lineage in their short-extending upper sections. Those native trout populations are so far still out of contact with the reservoir-dwelling trout. However, having in mind the resilience of trout featuring the migratory life-history, the outcome of this introduction could be deleterious for those natives very precious in conservational sense.

PENGETAHUAN PETERNAK TENTANG ESTRUS PADA SAPI ACEH DENGAN TERJADINYA REPEAT BREEDING DI KABUPATEN PIDIE

The study was aimed to determine the level of knowledge of farmers about cattle estrus Aceh with the occurrence of repeat breeding in Pidie District. Samples were obtained from secondary data reports for animal husbandry Department aceh Pidie 161 female cows study was. Carried out in the form of observational study with cross sectional approach. Primary data were collected by direct observation and interviews with questionnaires to farmers and inseminator. The data were analyzed descriptively. Chi Square test (X2) was used to determine the association between factors that cause, while Odds Ratio (OR) was used to calculate the strength of the association. The results of this study which has gained significantly associated (P less-than 0.05) on the incidence of repeat breeding is knowledge estrus with OR = 2.3. And the conclusion is. knowledge estrus against Aceh cattle repeat breeding associated with the occurrence of repeat positive or are associated. Keywords: knowledge estrus, repeat breeding, cattle Aceh

Prevalence, risk factors and constraints in control of repeat breeding in dairy animals of Punjab

The present study investigated the occurrence of repeat breeding (RB) and constraints in controlling this disease in cattle and buffalo in Punjab. Livestock owners/households (720) constituted the ultimate sampling units for the study. The dairy farmers were categorized into small (5–10 animals), medium (11–50) and large (>50) farmers. The overall prevalence of repeat breeding in the study area was 27.6%. It varied significantly with respect to herd size and categories of animals except in buffaloes. The highest prevalence was observed in crossbred cattle (41.8%), followed by indigenous cattle (32.0%) and buffaloes (17.6%). Repeat breeder animals were mostly high yielders (with >15 kg milk yield), calved mostly in winter season, having below average body condition score (BCS). No significant correlation was observed between parity (lactation number) and type of calving and prevalence of repeat breeding. The major constraint (rank I) perceived by farmers was culling of affected problematic cows, and lack of effective and accurate estrus detection in buffaloes. The other major constraints perceived in the study area were high cost of veterinary medicine, poor conception rate following artificial insemination and inaccessibility of qualified veterinarian. The lack of knowledge regarding animal nutrition and higher cost of branded feed available in the market were responsible for low body condition score of affected animals. Thus, a comprehensive policy and programmes involving various stakeholders are required for effective control of repeat breeding in Punjab.

Helpers improve fledgling body condition in bigger broods of cooperatively breeding African pygmy falcon

Universal predictions on the occurrence of cooperative breeding are still elusive. This breeding strategy is strongly linked to phylogeny; therefore, studies on species within groups where cooperative breeding is more prevalent could improve our understanding. Many diurnal raptors exhibit cooperative breeding, although occurrence rates are mostly based on anecdotal observations at nests. Here, we present a detailed study of the reproductive output and social organisation of the African pygmy falcon. Using data from six breeding seasons, we found helpers at 19% of nests. Helper presence had a positive effect on the body condition of the chicks as brood size increased, likely due to their contribution to feeding the chicks. Cooperative breeding groups were more likely to occur following years of higher reproductive output. Indeed, most of the helpers (77%) were non-dispersed offspring from the previous year, whereas the other helpers were immigrant adults (23%). We identified groups that included retained offspring (46%), immigrant adults (27%) or both types of helpers (27%). Breeding groups were also described as multi-male (65%), multi-female (26%) and multi-male-female (9%). Pygmy falcon group composition proved to be highly variable and diverse compared to other raptor species, in which helpers are generally unrelated adult males, showing that selection pressures leading to group formation in diurnal raptors may be more diverse than previously thought. Cooperative breeding occurs when more than two individuals contribute to raising a brood of young. It occurs in approximately 9% of bird species and it is particularly frequent in diurnal raptors. We studied the breeding performance and social organisation of the African pygmy falcon and found that they form breeding groups at 19% of the nests. These breeding groups included the breeding pair plus helpers that are either males or females. Helpers were also either adult immigrants or retained offspring. We also found that groups produced healthier fledglings than pairs and that groups are more likely to occur following years with high fledgling success. With this work, we expand the number of studies on raptor cooperative breeding and explore the fitness advantages of group breeding in this species as well as the mechanisms behind group formation.

Traces of cathode glow in atmospheric surface dielectric barrier discharge

Owing to the cathode layer properties in atmospheric surface dielectric barrier discharges (SDBDs), the discharges are sustained both for positive and negative voltage phase. There should be the cathode glow region where excited molecules or atoms are produced due to collision with the electrons before occurrence of electron-ion breeding in the cathode layer. Although a previous numerical study reported the generation of oxygen atoms, O(1D), O(3P), near an exposed electrode (EE) during the negative voltage phase, it is experimentally unattainable to verify the existence of the oxygen atoms because of the short length of the cathode layer with a thickness of approximately 20 μm at 1 atm in filamentary discharge mode. This work presents the experimental confirmation of trace(s) of O and N, which indicates the cathode glow, in a cathode layer in atmospheric SDBDs using ultra-fine surface polyimide as a dielectric in SDBD. Our results show that the cathode glow in atmospheric SDBD is located at approximately 5∼6 μm from EE in air.

Adult sex ratios and their implications for cooperative breeding in birds.

Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations in adult sex ratio (ASR, the proportion of males in the adult population) have been hypothesized to influence the occurrence of cooperative breeding because of the resulting surplus of one sex and limited availability of breeding partners, this hypothesis has not been tested across a wide range of taxa. By using data from 188 bird species and phylogenetically controlled analyses, we show that cooperatively breeding species have more male-biased ASRs than non-cooperative species. Importantly, ASR predicts helper sex ratio: in species with more male-biased ASR, helper sex ratio is also more male biased. We also show that offspring sex ratios do not predict ASRs, so that the skewed ASRs emerge during the period when individuals aim to obtain a breeding position or later during adulthood. In line with this result, we found that ASR (among both cooperatively and non-cooperatively breeding species) is inversely related to sex bias in dispersal distance, suggesting that the cost of dispersal is more severe for the further-dispersing sex. As females usually disperse further in birds, this explains the generally male-biased ASR, and in combination with benefits of philopatry for males, this probably explains why ASR is more biased in cooperatively breeding species. Taken together, our results suggest that a sex bias in helping in cooperatively breeding species relates to biased ASRs. We propose that this relationship is driven by sex-specific costs and benefits of dispersal and helping, as well as other demographic factors. Future phylogenetic comparative and experimental work is needed to establish how this relationship emerges.This article is part of the themed issue 'Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies'.

PREVALENCE OF REPEAT BREEDING AND ITS EFFECTIVE TREATMENT IN COWS AT SELECTED AREAS OF BANGLADESH

The objectives of the study were to determine the prevalence of repeat breeding and its associated risk factors in cows at selected areas of Bangladesh followed by determination of an effective treatment regime for those cows. Data were collected by interviewing the owner of the cows from 172 farms having 1524 breedable cows located at one Upazila of Mymensingh, Chittagong, Khulna, Satkhira, Bogra and Dhaka districts. A total of 122 repeat breeding cows were treated and randomly distributed into 5 experimental groups for different treatment regimes. The treatment regimes were (i) single AI with injection of 500 µg of gonadorelin, (ii) intra uterine infusion of 4.0 million i.u. penicillin daily for 3 days followed by single AI at next estrus, (iii) same time AI with double doses of semen, (iv) two times AI at 8 hours interval and (v) single AI without any intervention (used as control group). Information was collected for all treated cows for returning to estrus at 20-22 days post-AI. If the cow did not return to estrus at 20-22 days post-AI, the cows were examined for pregnancy by per rectal palpation of genital tract at 60-90 days post-AI. The pregnancy of the treated cows was used as the indicator of success of each treatment regime. The overall prevalence of repeat breeding in cows was 11.5%. The breed of cows, herd BCS and farm size influenced the prevalence of repeat breeding in cows. The age, parity, BCS and milk yield influenced the occurrence of repeat breeding in individual cows. The significantly higher proportion of cows recovered when AI was done using double doses of semen (52.8%) or single AI was done with GnRH administration (51.9%) than no intervention control (30.4%). In conclusion, repeat breeding cows may be inseminated with double doses of semen or with single AI with GnRH administration for improvement of conception.

Anuran responses to pressures from high-amplitude drought–flood–drought sequences under climate change

We measured changes in the occurrence, abundances and evidence of breeding of frogs to a sequence of severe drought–extreme wet–drought in south-eastern Australia, which is projected to characterize the regional climate in the coming decades. We collected data on anuran abundances, species richness and breeding by using aural surveys and visual searches in 80 waterbodies in 10 landscapes. We surveyed six times during the austral winter-springs of 2006 and 2007 (9–10 years into the 13-year ‘Big Dry’ drought), six times in the corresponding seasons of 2011 and 2012 (the ‘Big Wet’) and another six times in 2014 and 2015, which had lapsed into another intense dry period (‘post-Big Wet’). The relatively small gains in species occupancy rates and evidence of breeding achieved during the Big Wet following the Big Dry were eroded and reversed in the years after the Big Wet period, with several biotic measures falling substantially below the values for the Big Dry. The global prognosis is for long-term drying and warming, notwithstanding much geographic variation in the degree and temporal patterns of drying. Longer droughts with short periods of wet/benign conditions are projected for many parts of the world. For water-dependent fauna such as most amphibians, our results signal widespread declines in lowland regions experiencing such patterns. If droughts exceed lifespans of frogs, then resistance to drought will be so low that populations will plunge to levels from which the short periods of more benign conditions will be insufficient to enable substantial recovery.

Management Practices Followed by Dairy Farmers in Rural and Urban Areas of Bathinda District in Punjab

A field study was concluded to note down the various animal husbandry practices followed by the dairy farmers in rural and urban areas in Bathinda district of Punjab. It was found that about 75 per cent of respondents kept the animals in commercial type of housing system whereas 69 per cent animal sheds were nearby to the dwelling of the farmers and 83 per cent of the farmers provided concrete manger. Majority of the respondents (58%) followed the individual feeding system, cultivated fodder crops (68%) for feeding to dairy animals throughout the year and only 25 per cent of farmers produce non-legume fodder. Similarly, while use of mixed fodder (both legume and non-legume) restricted to only 15 per cent. The health status was maintained by using regular vaccination (91%), veterinary facilities (81%) and artificial insemination (65%) by the respondents. Majority of respondents in the study area felt the constraints of lack of capital, high cost of shed construction, high feed costs and occurrence of repeat breeding in cross bred cattle.

Breeding behaviour in the Spangled Drongo Dicrurus bracteatus

Over a period of five breeding seasons (between November 2008 and January 2013) the breeding behaviour—including nest-site selection, nest building, incubation and care of nestlings and fledglings—of the Spangled Drongo Dicrurus bracteatus was observed at Coowonga on the central Queensland coast, and from this the breeding success was estimated. The breeding season was from November to January, with a consistent start date from year to year. The incubation and nestling periods were also consistent from year to year. A nest was generally positioned in a tree near a clearing and in the outer part of that tree. Several factors contributed to nest-site selection: nest-tree species, habit and height, diameter of the tree’s outer branches, availability of dead branches, proximity of the nest-tree to a clearing and to water, and height of the nest above the ground. New findings were the frequent attachment of a nest to dead twigs and the consistent placement of a nest on the first branch below the spreading canopy of the tree. The occurrence of colonial breeding was more difficult to determine, with many features of this behaviour (such as group nesting and co-operative defence against predators) being evident, but nests were widely dispersed over a large area. Rotation of nest-sites may be used to minimise predation, with some Drongos using a nest-site one year, but not the next, and then returning to that nest-site the following year.

Environmental factors associated with amphibian breeding in streams and springs: effects of habitat and fish occurrence

Streams are among the most threatened aquatic habitats for amphibians. Amphibians often demonstrate a complex community structure and investigations are mainly performed on pond-dwelling species, whereas data regarding stream-dwelling species is still scarce. The aim of this study was to evaluate the relevance of stream features and the effects of the occurrence of predatory fish on the community structure of amphibians. To assess the occurrence of breeding among amphibians (in Northern Apennine streams), sampling was performed on 57 stream and spring sites between early March and late May 2014. The research process recorded the presence of four breeding species (Salamandra salamandra, Salamandrina perspicillata, Bufo bufo, and Rana italica) and discovered that the community structures of amphibians were significantly connected to different habitat features. The investigation showed that fish presence is the primary habitat feature that affects the communities of amphibians: B. bufo was the only amphibian species not affected by fish presence, while the other species avoided sites with fish. Sun exposure, depth of water and slope inclination played important roles in affecting amphibian breeding. Our study confirms that fish presence in small streams can be detrimental for different amphibian species.

South Africa's coastal-breeding white-breasted cormorants: population trends, breeding season and movements, and diet

White-breasted cormorants Phalacrocorax [carbo] lucidus breed around South Africa's coast and at inland localities. Along the coasts of the Northern, Western and Eastern Cape provinces, numbers breeding were similar during the periods 1977–1981 (1 116 pairs at 41 localities) and 2008–2012 (1 280 pairs at 41 localities). Along the coast of KwaZulu-Natal (not counted in 1977–1981), 197 pairs bred at nine localities in 2008–2012, when the overall number breeding around South Africa's coastline was about 1 477 pairs. Between the two study periods, numbers decreased in the Northern and Western Cape provinces following the loss of several breeding localities, but they increased in the Eastern Cape. In the Western Cape, however, numbers were stable east of Cape Agulhas and at nine well-monitored West Coast localities that were surveyed from 1978 to 2012. White-breasted cormorants breed throughout the year, with breeding at some localities more seasonal than at others and the timing of peaks in breeding varying at and between localities. In the vicinity of Saldanha Bay/Langebaan Lagoon (Western Cape), in Algoa Bay (Eastern Cape) and in northern KwaZulu-Natal, it is likely that birds moved between breeding localities in different years, although breeding often occurred at the same locality over several years. Human disturbance, presence of predators, competition for breeding space and occurrence of breeding by other waterbirds may influence movements between colonies. Securing sufficient good habitat at which white-breasted cormorants may breed will be important for conservation of the species. The species may breed at an age of 4 years, possibly younger. The bulk of their diet around South Africa's coast consists of inshore marine and estuarine fish species that are not intensively exploited by humans.