Breeding Ecology Research Articles

Amended diagnosis and redescription of Pristimantis marmoratus (Boulenger, 1900) (Amphibia: Craugastoridae), with a description of its advertisement call and notes on its breeding ecology and phylogenetic relationships

The frog Pristimantis marmoratus was originally described as Hylodes marmoratus by George A. Boulenger in 1900 based on a single specimen reported to have been collected at the foot of Mount Roraima in Guyana in 1898. We herein discuss the exact location of the type locality of P. marmoratus and provide a redescription of the species based on new material from Kaieteur National Park and from the slopes of Maringma-tepui in Guyana. We also describe the previously unknown vocalization and breeding ecology of the species, and conducted an exploratory molecular analysis of the phylogenetic relationships within the genus Pristimantis represented by the members of the “unistrigatus species group” in the Guiana Shield. Pristimantis marmoratus is a small-sized species mainly distinguished from its known Guiana Shield congeners by the combination of F I < II, SVL ≤ 20.4 in males, presence of vocal slits in males, granular/pustulate dorsal skin with well-developed scapular ridges, basal webbing between fingers, fringes on fingers and toes, crossed iris, diffuse yellow or pale green wash on groin, and absence of flashy colour on axillary/pre-axillary region. The advertisement call consists of a single note repeated at a rate of ca 11 calls/min with a dominant frequency ranging from 2756 to 3101 Hz. Pristimantis marmoratus is primarily arboreal, exclusively active at dusk, and probably restricted to the pristine rainforests of the Pantepui uplands and highlands, east of the Gran Sabana between ca 600 and 1800 m above sea level. Preliminary molecular analyses recovered Pristimantis marmoratus as sister to an unnamed species from the Eastern Guiana Shield. On grounds of the newly established distributional extent we suggest maintaining the IUCN conservation status as Least Concern.

Blood parasite infections in a wild population of ravens (Corvus corax) in Bulgaria

BackgroundBlood parasites have been studied intensely in many families of avian hosts, but corvids, a particularly cosmopolitan family, remain underexplored. Haemosporidian parasites of the common raven (Corvus corax) have not been studied, although it is the largest, most adaptable, and widespread corvid. Genetic sequence data from parasites of ravens can enhance the understanding of speciation patterns and specificity of haemosporidian parasites in corvids, and shed light how these hosts cope with parasite pressure.MethodsA baited cage trap was used to catch 86 ravens and a nested PCR protocol was used to amplify a 479 bp fragment of the haemosporidian cytochrome b gene from the samples. The obtained sequences were compared with the MalAvi database of all published haemosporidian lineages and a phylogenetic tree including all detected raven parasites was constructed. An examination of blood smears was performed for assessment of infection intensity.ResultsTwenty blood parasite lineages were recovered from ravens caught in a wild population in Bulgaria. The prevalence of generalist Plasmodium lineages was 49%, and the prevalence of Leucocytozoon lineages was 31%. Out of 13 detected Leucocytozoon lineages six were known from different corvids, while seven others seem to be specific to ravens. A phylogenetic reconstruction suggests that Leucocytozoon lineages of ravens and other corvids are not monophyletic, with some groups appearing closely related to parasites of other host families.ConclusionsSeveral different, morphologically cryptic groups of Leucocytozoon parasites appear to infect corvids. Ravens harbour both generalist corvid Leucocytozoon as well as apparently species-specific lineages. The extraordinary breeding ecology and scavenging lifestyle possibly allow ravens to evade vectors and have relatively low blood parasite prevalence compared to other corvids.

Nest-Site Characteristics and Nesting Success of the Chestnut Thrush

Nest-site characteristics may affect the daily survival rate of avian nests. We monitored the nests of Chestnut Thrush Turdus rubrocanus breeding in an agricultural landscape near the Lianhuashan Natural Reserve (central China) during the breeding seasons of 2013 and 2014. We describe the Chestnut Thrush's breeding ecology and used logistic-exposure methods and an information theoretic approach to assess the factors influencing daily survival rates of nests. Results from model averaging indicated that daily survival rates of nests consistently decreased from habitat edge to interior, contradicting the classic edge effect hypothesis describing predation of avian nests. Concealment of nests from below was positively correlated with nest daily survival rates, whereas concealment from the side and from above were not. These results suggest that determining the various effects of vertical and/or horizontal concealment on nest survival rates may help us assess the variation in the ability of local predators to detect nests.

Экология размножения большой синицы (Parus major) в островном лесу Центрального Черноземья (на примере Воронежского заповедника)

Экология размножения большой синицы (Parus major) в островном лесу Центрального Черноземья (на примере Воронежского заповедника)

Breeding observations of the Black-winged Kite Elanus caeruleus (Desfontaines, 1789) in Iraq

This study was conducted in order to examine the breeding occurrence of the Black-winged Kite Elanus caeruleus at several locations in Al-Qadisiyah Province of the Middle Euphrates region, Iraq, in 2017. Three active nests were regularly observed from April through July 2017. All three nests were located in date palms Phoenix dactylifera, close to the center of the tree, at the average height of 7.73 m above the ground. The clutch size of four eggs and the 100% hatching success were recorded for all the three nests. The mean fledging success reached 92% for the three nests. The current study contributes to the knowledge of the global breeding distribution of the Black-winged Kite and sheds some light on the breeding ecology of the species in Iraq.

Importance of Breeding Ecology and Territorial Behaviour of Indian Black Robin (Saxicoloides fulicata leucoptera) for its Conservation

Indian Black Robin (Saxicoloides fulicata leucoptera) is one of the territorial bird found in scrub forest, rocky areas, open grasslands and near human residence and distributed throughout the country in all climatic zones. Breeding success of birds can be depended on the size of the territory. Territory size can be varying according to breeding season and different locations they occupied. Present study attempted to understand the breeding ecology and territorial behavior of black robin in both breeding and non-breeding seasons. The data were collected using scan sampling and focal animal sampling from 2014 to 2017 in adjacent to the Mihintale sanctuary. The behavioral and territory variations were checked by using a dummy of black robin. ArcGIS v10.3 and Minitab v17 were used for data analysis. The breeding season of black robin lasted nearly three months twice a year from March to June and July to September. Courtship behaviour was started beginning of April and nest building was performed by both male and female. The nest building period averaged 13.25±0.96 days. Ten nests were recorded within the study period whilst 4 of them were successful and 6 were pseudo nests. Nests were observed at different places such as rocky areas, rock fragments and joisters of resident places. The clutch size was 2-4 and eggs were whitish in background with small brownish blotches. Average incubation period was 11±3.4 days. Both male and female fed the chicks after hatching. Foraging sites were mostly nearby roads, human associated places and live foliage. As a percentage, male used to feed chicks 69.23% and female 30.77% within the observed period. There were 12 territories recorded within the study period. The territorial areas were changed according to the members of the group and the breeding season. Territory size ranged from 617 m2 to 5,050 m2 and smaller territories were recorded during the non breeding period while sizes were larger during the breeding period. Results suggest that this species require sufficient habitats to demarcate their territory and nesting. Hence maintain the gardens and shady areas are recommended to conserve this species in domestic areas. Keywords: Black Robin, Territory, Nests, Conservation

Breeding phenology and nest survival of Cinereous (Circus cinereus) and Long-winged (C. buffoni) Harriers in the agricultural landscapes of north-east Patagonia, Argentina

ABSTRACTWe present novel data on breeding ecology and nest survival of the Cinereous (Circus cinereus) and Long-winged (C. buffoni) Harriers in modified grasslands of southern Argentina and we evaluate variations in daily nest survival rates (DSR) in relation to temporal and habitat variables. We studied three mixed nesting colonies embedded in agricultural landscapes along a road. We found that DSR decreased linearly with time of breeding and increased with vegetation height above the nest and the distance to the road. This is the first and most complete reproductive study concerning two species of conservation concern, namely the Cinereous and Long-winged Harriers in Patagonia. Our study provides valuable and novel insights into the population dynamics of these little-known species.

Nest-site characteristics and aspects of the breeding biology of the endangered Timneh Parrot Psittacus timneh in Guinea-Bissau

Timneh Parrots Psittacus timneh are endemic to the moist forests of West Africa. Concerns over rapid declines in populations due to overharvesting for the pet trade and forest loss prompted the species’ categorisation as Endangered on the IUCN Red List of Threatened Species in 2016. Despite these threats, few data exist on their biology in the wild, impeding the development of effective conservation initiatives to protect populations. One of the few recorded breeding sites for this species occurs in the Bijagós Archipelago in Guinea-Bissau, where chicks have been historically harvested from nests and forest clearance for agriculture is common. We investigated the breeding ecology of Timneh Parrots in the Bijagós Archipelago focusing on two islands that harbour the densest populations. Specifically, we describe nest-site characteristics, breeding phenology and reproductive productivity. Timneh Parrots were found to use secondary nest cavities in 17 species of trees, predominantly nesting in trees between 20 m and 50 m in height. Nest cavities were generally aggregated, with a density of up to 14 nests ha−1 in some areas, although nests also occurred in isolated large trees. The distribution of nests likely reflected a heterogeneous distribution of large trees containing suitable nest cavities, emphasising the importance of protecting mature trees. Nesting efforts were initiated between early January until late March, suggesting that nest surveillance efforts to deter poaching can be efficiently focused at a small number of key sites during February to May each year, when fledgling chicks are most likely to be present. These data further suggest that the population may be limited by the availability of suitable nest cavities and that the installation of artificial nest cavities could help increase the breeding population.

Nest-site selection and breeding ecology of Streaked Wren-Babbler (Napothera brevicaudata) in a tropical limestone forest of southern China

BackgroundThe breeding information of most birds in Asian tropical areas, especially in limestone forests, is still poorly known. The Streaked Wren-Babbler (Napothera brevicaudata) is an uncommon tropical limestone bird with a small range. We studied its nest-site selection and breeding ecology, in order to understand the adaptations of birds to the conditions of tropical limestone forest in southern China.MethodsWe used methods of systematical searching and parent-following to locate the nests of the Streaked Wren-Babbler. We measured characteristics of nest sites and rock cavities. Data loggers and video cameras were used to monitor the breeding behavior.ResultsAll the observed nests of the Streaked Wren-Babbler were placed in natural shallow cavities or deep holes in large boulders or limestone cliffs. The great majority (96.6%) of Streaked Wren-Babbler nests had three eggs with an average fresh weight of 3.46 ± 0.43 g (n = 36, range 2.52‒4.20 g). Most (80.4%) females laid their first eggs between March and April (n = 46). The average incubation and nestling period of the Streaked Wren-Babbler was 10.2 ± 0.4 days (n = 5, range 10‒11 days) and 10.5 ± 0.8 days (n = 6, range 9‒11 days), respectively. Most (87.9%) nests had at least one nestling fledge between 2011 and 2013 (n = 33).ConclusionsOur study suggests that several features of the breeding ecology of the Streaked Wren-Babbler, including building nests in rocky cavities, commencing breeding earlier than most species, and reducing foraging times during the incubation period, are well-adapted to the unique habitat of tropical limestone forest.

Turn-taking in cooperative offspring care: by-product of individual provisioning behavior or active response rule?

For individuals collaborating to rear offspring, effective organization of resource delivery is difficult because each carer benefits when the others provide a greater share of the total investment required. When investment is provided in discrete events, one possible solution is to adopt a turn-taking strategy whereby each individual reduces its contribution rate after investing, only increasing its rate again once another carer contributes. To test whether turn-taking occurs in a natural cooperative care system, here we use a continuous time Markov model to deduce the provisioning behavior of the chestnut-crowned babbler (Pomatostomus ruficeps), a cooperatively breeding Australian bird with variable number of carers. Our analysis suggests that turn-taking occurs across a range of group sizes (2–6), with individual birds being more likely to visit following other individuals than to make repeat visits. We show using a randomization test that some of this apparent turn-taking arises as a by-product of the distribution of individual inter-visit intervals (“passive” turn-taking) but that individuals also respond actively to the investment of others over and above this effect (“active” turn-taking). We conclude that turn-taking in babblers is a consequence of both their individual provisioning behavior and deliberate response rules, with the former effect arising through a minimum interval required to forage and travel to and from the nest. Our results reinforce the importance of considering fine-scale investment dynamics when studying parental care and suggest that behavioral rules such as turn-taking may be more common than previously thought.Significance statementCaring for offspring is a crucial stage in the life histories of many animals and often involves conflict as each carer typically benefits when others contribute a greater share of the work required. One way to resolve this conflict is to monitor when other carers contribute and adopt a simple “turn-taking” rule to ensure fairness, but natural parental care has rarely been studied in sufficient detail to identify such rules. Our study investigates whether cooperatively breeding chestnut-crowned babblers “take turns” delivering food to offspring, and (if so) whether this a deliberate strategy or simply a by-product of independent care behavior. We find that babblers indeed take turns and conclude that part of the observed turn-taking is due to deliberate responsiveness, with the rest arising from the species’ breeding ecology.

Breeding ecology and habitat selection of Merlin Falco columbarius in forested landscapes

Capsule: Long-term trends in Merlin Falco columbarius breeding performance remained stable during a period of extensive afforestation in Ireland, where Merlin predominantly select conifer plantations for nesting.Aims: To determine breeding performance and habitat selection of Merlin in a landscape significantly altered by afforestation.Methods: We compiled data on Merlin to determine long-term trends in breeding performance and to examine habitat selection in a country with one of the fastest rates of afforestation in Europe.Results: Merlin predominantly nested in trees (99.5%; n = 183 pairs), with a strong preference for conifer plantations, which accounted for over 12 times more nests than expected by random selection. Moors and heathland were strongly selected as land-uses adjacent to nest sites. Most nests were located within 10 m of the forest edge, and in forests aged between 31 and 40 years. Merlin showed positive selection for moors and heathland, peat bogs and natural grasslands within breeding territories, and breeding success was positively related to the proportion of these land-uses surrounding nests. Breeding was successful for 74% of nests (n = 300), and mean productivity was 2.1 young per breeding attempt (n = 265) between 1982 and 2014. Breeding parameters remained constant over the 33-year study period, despite an increase of more than 75% in forest cover during this time.Conclusion: Merlin breeding performance showed no long-term effects of increased afforestation. Although Merlin predominantly nested in conifer plantations, the presence of nearby open suitable foraging habitats influenced nest site selection and breeding success. The nesting preference of Merlin makes them vulnerable to disturbance from forest operations, which requires mitigation.

Breeding Ecology of the Masked LaughingthrushGarrulax perspicillatus, a Cooperative Breeder in Central China

In this paper, we provide for the first time a detailed description of the breeding ecology of the Masked Laughingthrush Garrulax perspicillatus. Our findings indicate that this species is a cooperative breeder with retained offspring. Flocks of Masked Laughingthrushes occurred in winter; these split into smaller breeding groups during the spring. The size of breeding groups varied from three to six individuals (mean = 3.8 individuals, n = 26). Clutches were initiated between early March and early August. Clutch size averaged 3.3 eggs and ranged from two to five (n = 18). The incubation period lasted on average 13.2 days (n = 9) and chicks left the nest after 12 days (n = 23). Breeding groups produce 2–3 broods per year (n = 2). 82.8% of 58 breeding attempts resulted in fledged offspring. Helpers were observed participating in nest-building, incubation and provisioning. The size of breeding groups was significantly related to both the overall frequency of feeding trips to the nest and brood size at fledging, with a higher frequency of feeding trips and more fledglings for larger groups. Hence, both breeders and helpers may potentially derive fitness benefits from helping at the nest.

Distribution and breeding ecology of the Ferruginous Duck Aythya nyroca in Algeria

We conducted a survey of the distribution of Ferruginous Duck Aythya nyroca across Algeria and analysed the influence of nest-site characteristics on nesting success at a Ramsar site, Lake Tonga. The species was found to occupy different wetlands (freshwater lakes, brackish marshes and salt lakes) across three major climatic belts (subhumid coastal strip, semi-arid Hauts Plateaux and arid Sahara). Mean clutch size of successful nests was 13.3 ± 6.0 eggs (N = 26) with a hatching rate of 74% for successful clutches. Nesting success was recorded for 44% of nests with clutch desertion (72.7%) accounting for the majority of failed clutches. Egg size of the study population, which breeds at the southern limit of the species’ range, was significantly smaller than that of its northerly counterparts. Clutch size was negatively related to egg size and positively associated with depth of water below the nest, suggesting that older, more experienced or high-quality birds monopolised the safest sites. Successful clutches were significantly associated with tall vegetation, suggesting that when nesting is carried out mainly on offshore floating islets, protection against aerial predators and heat stress determine nesting outcome. Conspecific brood parasitism was significantly and positively associated with deferred egg-laying and smaller egg size, suggesting an age-dependent mechanism.

First data on breeding ecology of Red-billed Pied TanagerLamprospiza melanoleuca, including the nest and egg

First data on breeding ecology of Red-billed Pied Tanager<i>Lamprospiza melanoleuca</i>, including the nest and egg

Ecology of two Pittas (Pitta soror and Pitta nympha) in limestone forests of South China

ABSTRACTThe ecology and life history of bird species inhabiting limestone forests, which are under major conservation threats, is currently poorly known. To cover this gap of knowledge, in this study we report for the first time on several aspects of the breeding ecology of the Blue-rumped Pitta (Pitta soror) and the Fairy Pitta (P. nympha) inhabiting two typical limestone forests of south China. The mean density of Fairy Pittas in our study locations was 3.13 ± 2.82 and 1.05 ± 2.09 individuals/km2. The Blue-rumped Pitta was common in Nonggang and showed a mean density of 4.67 ± 2.44 individuals/km2, yet was absent in the other. We found nine nests between February 2009 and June 2015, including five of the Blue-rumped Pitta and four of the Fairy Pitta. Blue-rumped Pittas laid 4.8 ± 0.4 eggs with a mean fresh mass of 8.10 ± 0.40 g. Fairy Pittas had a clutch size of 5.2 ± 0.45 eggs with a mean fresh mass of 6.03 ± 0.22 g. Blue-rumped and Fairy Pitta parents fed their nestlings 4.0 ± 1.2 times and 3.9 ± 1.5 times per hour, respectively. Earthworms were the most common food item delivered to nestlings by Blue-rumped (93.6%) and Fairy Pitta (91.2%) parents. Blue-rumped Pittas bred successfully in 40% of nests (two of five), whilst in the case of Fairy Pittas nest success reached 75% (three of four). The two Pittas had larger clutch sizes than in southern populations of the same species and also than most other bird species inhabiting limestone forests. This would imply that Pittas show differences in life history traits within limestone ecosystems.

Temporal differences in breeding site use between tits and mice

ABSTRACT Describing the interactions among cavity breeders is key to understanding their breeding ecology. In this study the temporal difference in cavity use between the great tit, Parus major (Linnaeus, 1758) and the small Japanese field mice, Apodemus argenteus (Temminck, 1845) is investigated, as a first step for clarifying the interaction between bird and mammal cavity breeders. Forty-seven nest boxes were installed on tree trunks in two urban forests of Hokkaido Island, Japan, and the breeding nests of tits and mice were found in 34 and 11 boxes, respectively. The tits used the nest boxes throughout the breeding season, from May to July. In contrast, mice breeding nests were found in the last half of the breeding season, from July to October. Our results showed that field mice rarely used boxes during the tits’ breeding season. This study provides important information, such as temporal differences in breeding site use between tits and mice.

Nest position, breeding success and diet of the Black-crowned Night Heron, Nycticorax nycticorax in the Anzali Wetland, Northern Iran (Aves: Ardeidae)

Breeding ecology of the Black-crowned Night Heron (Nycticorax nycticorax) was studied in a mono-specific colony in the Anzali wetland, Northern Iran during the breeding season of 2016. The breeding period lasted from mid-May to late July. The average clutch size was 3.1±0.6 eggs and the breeding success 77.6%. No significant differences were found between nests built on trunks and those built on branches of trees. The clutch size and breeding success appeared to be independent of the structural variables of the nesting site (diameter of trees, height from the ground, height of nests from the canopy, nest number per tree, location of nests on trunks and branches). No significant difference was found between the timing of the start of incubation and the height of nests above the ground. The average vertical and horizontal distances between nests was one metre. Fish, particularly Carassius gibelio, dominated the diet of the nestlings.

Sooty FalconFalco concolorreproduction and population dynamics on the islands in the Sea of Oman

Knowledge of demographic parameters affecting population dynamics is critical to the formulation of effective conservation strategies. Sooty FalconFalco concoloris a little‐studied, Near‐threatened species; estimates of global population size and trend for this species are uncertain. They lay eggs during mid‐summer and sometimes nest in colonies. This unusual breeding ecology suggests that demographic parameters driving their population growth rate may differ from those of most other falcons. We studied Sooty Falcon reproduction at breeding aggregations on Fahal Island and the Daymaniyat islands in the Sea of Oman during 2007–2014, modelled population growth and identified important life history parameters using elasticity analysis. The mean (± se) clutch and brood size was 2.83 ± 0.06 and 2.11 ± 0.07, respectively. Overall, 11.7% of nests failed between the egg and nestling stages, and the failure rate differed significantly between Fahal and the Daymaniyats, and across years. The mean proportion of eggs that hatched annually was 0.66 ± 0.02, and broods were significantly smaller on the Daymaniyats than on Fahal. Falcons on Fahal Island had a higher rate of hatching, a higher rate of nests that produced at least one chick, and produced more chicks per nest than on the Daymaniyats. We suggest that Fahal's proximity to the mainland gives breeding Sooty Falcons access to a more plentiful and stable source of food, especially during the period between arrival from the wintering grounds and the onset of the autumn migration of prey birds, resulting in the better reproductive rates for falcons on Fahal Island, relative to those on the Daymaniyat Islands. The annual asymptotic population growth rate (λ) was 0.87 (95% confidence interval (CI) 0.75–0.99), suggesting a declining population, although Sooty Falcons enjoyed a slightly higher population growth rate on Fahal than on the Daymaniyats. Because our study population is on the edge of the breeding range and is isolated from other breeding areas, measures to improve reproductive success of Sooty Falcons breeding on the islands in the Sea of Oman could be important for conservation of Sooty Falcons in Oman.

First observations on the breeding ecology of invasive Dryocoetes himalayensis Strohmeyer, 1908 (Coleoptera: Curculionidae: Scolytinae) in its introduced range in Europe - Short communication

The invasive bark beetle species Dryocoetes himalayensis Strohmeyer, 1908, originated from Himalayan regions, arrived in Europe in the 1970s, and is now considered to be established in several European countries (Czech Republic, France and Switzerland). This species is reported to develop in walnut (Juglans regia Linnaeus) and pear (Pyrus lanata D. Don) in the region of its origin; however, to date, there has been no information regarding its host trees and breeding ecology in its introduced range. The present paper reports the development of D. himalayensis in declining black walnut trees (Juglans nigra Linnaeus) in a floodplain forest of southern Moravia (Czech Republic). The galleries were associated with basal parts of trunks of various diameters (7–45 cm) and were accompanied by dark necrotic areas and noticeable outflow of black fluid from beetle entrance holes. Further studies on the bionomics of this species are necessary to clarify its potential status as a pest of walnut trees.

Agri-environmental measures and the breeding ecology of a declining farmland bird

Agricultural intensification is a key cause of the population declines shown by many farmland bird species across Europe. Changes in land management through agri-environment schemes (AES) are frequently cited as the best tool to reverse these trends, to date however they have received mixed support. This study tested whether AES options in England that provide winter seed food or insect-rich foraging during the breeding season, were associated with improved breeding performance in tree sparrow, Passer montanus, and/or the formation of larger breeding colonies. Breeding attempts (n=428) representing 210 pairs of tree sparrow comprising 22 colonies were compared in Wiltshire, England in 2013 and 2014. The area of margin AES, an insect-rich habitat, was positively correlated with fledgling success per breeding attempt and per breeding pair. Colony size increased with increasing wild bird seed mix AES area, a winter seed food resource, but this option negatively affected hatching success and the number of fledglings produced per breeding attempt. The observed association between colony size and this habitat was expected given that wild bird seed mixtures provide important seed food resources for granivorous birds during winter. The negative correlation with fledgling success, on the other hand, requires further investigation to determine whether this relationship relates to a lack of invertebrate and seed food during the breeding period. These results highlight the importance of providing a suite of AES habitats that are appropriately located to deliver both overwintering and breeding requirements of target, declining farmland birds.