Nest Protection Research Articles

Protecting nests of the Critically Endangered South Pacific loggerhead turtle Caretta caretta from goanna Varanus spp. predation

AbstractThe South Pacific subpopulation of the loggerhead turtle Caretta caretta is categorized as Critically Endangered on the IUCN Red List because of significant population declines. Five Queensland beaches support high-density nesting of this subpopulation, but egg and hatchling survival are low at some beaches because of feral and native terrestrial predators. We quantified predation of loggerhead turtle eggs by two species of goanna, Varanus panoptes and Varanus varius, at Wreck Rock beach, one of the turtle's major nesting beaches. In addition, we conducted an experiment to determine the efficacy of a nest protection device. Predation rates at Wreck Rock beach were 15.2% for treatment and 45.8% for non-treatment clutches during the 2013–2014 nesting season. A higher probability of predation (64%) was predicted for the northern beach. Although nests were only partially predated (16.4% of the total number of eggs), nest loss to predators and beach erosion (caused by a cyclone) was 91.7%. If left unmanaged, the cumulative impact of predation and other threats, including those exacerbated by climate change, can cause unsustainable loss of loggerhead turtle nests. This study provides one of the first quantitative data sets on rates of loggerhead turtle clutch predation in the South Pacific. It enhances our understanding of goanna predation impacts and identifies an efficient predator exclusion device for mitigating the effects of terrestrial predators at Wreck Rock beach, and for protecting marine turtle nests across northern Australia and globally.

Hematology and plasma biochemistries in the Blanding's turtle (Emydoidea blandingii) in Lake County, Illinois.

Chelonians are one of the most imperiled vertebrate taxa on the planet due to changes in the environment, anthropogenic influences, and disease. Over the last two decades, conservation strategies including nest protection, head-starting and meso-predator control have been successfully adopted by the Lake County Forest Preserve District for a population of state-endangered Blanding’s turtles (Emydoidea blandingii) in Illinois. Only recently have efforts expanded to assess the effects of management action on turtle health. The objectives of this study were to 1) establish reference intervals for 16 hematologic and plasma biochemical analytes in free-ranging Blanding’s turtles, 2) characterize demographic and temporal drivers of clinical pathology values including age class, sex, month, and year, and 3) describe bloodwork differences between a managed (SBCP) and unmanaged (IBSP) study site. Hematology and plasma biochemistries were performed for 393 turtles from 2017–18 at two sites in the Lake Plain region. Subject or population-based reference intervals were established based on the index of individuality per American Society for Veterinary Clinical Pathology guidelines. Analytes differed by age class [packed cell volume (PCV), total solids (TS), total white blood cell counts (WBC), heterophils, lymphocytes, heterophil:lymphocyte ratio (H:L), total calcium (Ca), calcium:phosphorous (Ca:P), bile acids (BA), aspartate aminotransferase (AST)], sex [H:L, Ca, phosphorus (P), Ca:P, creatine kinase (CK)], month [eosinophils, H:L, Ca, P, uric acid (UA), AST], and year [PCV, WBC, lymphocytes, basophils, H:L, Ca, P, UA]. Several analytes also varied by site [PCV, TS, monocytes, eosinophils, P, UA, AST], suggesting that health status may be affected by habitat management or lack thereof. The results of this study provide a baseline for ongoing health assessments in this region as well as across the Blanding’s turtle range.

Emergence Timing of Leatherback Hatchlings (Dermochelys coriacea) at Sandy Point National Wildlife Refuge, 2010–2014

Leatherback sea turtles (Dermochelys coriacea) are listed as Vulnerable globally by the International Union for Conservation of Nature. To preserve this species, we must protect them during several life stages, including protecting hatchlings emerging from nests. We studied the timing of emergence of leatherback hatchlings at Sandy Point National Wildlife Refuge, an area created for the protection of this species. We surveyed 524 nests in 2010–2014 and evaluated the time that hatchlings began emerging from the surface of the sand, the time that the last hatchling in the group finished emerging from the sand, the incubation duration of each nest (number of days between deposition and first emergence), and the number of hatchlings in the initial pulse of emergence. In situ clutches (those occurring naturally and not manipulated by location) had an incubation period of 61.4 ± 21.1 d (mean ± SD; n = 332) and emerged from 1825 to 1906 hrs. The incubation duration varied significantly from relocated clutches (those that had been moved at deposition because of erosion threats), had an incubation period of 60.0 ± 2.7 days (n = 192), and emerged from 1827 to 1903 hrs (on average, for all years combined; p < 0.0001). These nests yielded 36.6 ± 21.1 first-emergence hatchlings from in situ clutches, which was different from relocated clutches (14.9 ± 13.6 first-emergence; p < 0.0001). Other studies have found that hard-shelled sea turtles all begin emerging once the sun sets and continue emerging throughout the night. In contrast, we found that leatherback sea turtle hatchlings emerge earlier in the evening, at least at Sandy Point. During the seasons sampled, emergence often began before sunset (between 1834 and 1859 hrs) and hatchlings usually did not continue to emerge through the night. To allocate resources most effectively, beach management programs at Sandy Point National Wildlife Refuge should be maximized between 1700 and 2000 hrs, the period when most hatchlings are emerging and require the most protection from predators. This work provides important information about the timing of leatherback emergence and may be applicable to other leatherback nesting beaches where predation may be a problem. These findings can help ensure that nest protection programs maintain efficiency and protect hatchlings during their vulnerable crawl to the sea.

Low productivity and unsuitable management drive the decline of central European lapwing populations

AbstractDespite the protective measures that have been implemented to increase the productivity of meadow birds, populations are still declining in most breeding and wintering areas. We therefore still do not know how large the protective efforts need to be to curb the decline of the meadow bird populations. By taking advantage of monitoring data from the populations of lapwings in the Netherlands (NL) and one region in Germany [Schleswig‐Holstein (SH)], we investigated the demographic drivers responsible for the decline of the populations and evaluated the impact of protective measures. In these populations, some nests are marked with sticks such that they are not destroyed by farming activity. We analyzed the data with integrated population models and show that average demographic rates were similar in the two populations. Retrospective analyses demonstrated that variation in productivity most strongly impacted population dynamics and that its variation was influenced by the local environments. Our results confirmed that low productivity (0.55 and 0.46 fledglings per pairs in SH and NL, respectively) was the main reason for the decline of the lapwing populations. Productivity of 0.76 (SH) and 0.91 (NL) fledglings per pairs would be required to stabilize the populations. The implemented nest protection had a positive effect on nest success, but did not improve chick survival, and consequently the effect on population growth rates remained insufficient. The population growth rate in NL would increase by only 2% if all nests were protected. Our results suggest that protective measures should prioritize the reduction in predation and the improvement of chick habitat by promoting heterogeneous swards combining tall vegetation for hiding and short and open vegetation for foraging.

Rodent mothers increase vigilance behaviour when facing infanticide risk

Infanticide, the killing of unrelated young, is widespread and frequently driven by sexual conflict. Especially in mammals with exclusive maternal care, infanticide by males is common and females suffer fitness costs. Recognizing infanticide risk and adjusting offspring protection accordingly should therefore be adaptive in female mammals. Using a small mammal (Myodes glareolus) in outdoor enclosures, we investigated whether lactating mothers adjust offspring protection, and potential mate search behaviour, in response to different infanticide risk levels. We presented the scent of the litter’s sire or of a stranger male near the female’s nest, and observed female nest presence and movement by radiotracking. While both scents simulated a mating opportunity, they represented lower (sire) and higher (stranger) infanticide risk. Compared to the sire treatment, females in the stranger treatment left their nest more often, showed increased activity and stayed closer to the nest, suggesting offspring protection from outside the nest through elevated alertness and vigilance. Females with larger litters spent more time investigating scents and used more space in the sire but not in the stranger treatment. Thus, current investment size affected odour inspection and resource acquisition under higher risk. Adjusting nest protection and resource acquisition to infanticide risk could allow mothers to elicit appropriate (fitness-saving) counterstrategies, and thus, may be widespread.

Monitoring corticoid metabolites in urine of white-tailed sea eagles: Negative effects of road proximity on breeding pairs

The white-tailed sea eagle (Haliaeetus albicilla) is known to be sensitive to disturbance. To better understand potential stressors, we measured corticosterone metabolite levels in H. albicilla excreta and recorded the nest success of breeding pairs. We tested the ability of four enzyme immunoassays (EIA) to measure urinary glucocorticoid metabolites (uGM) in the excreta of one adult female eagle subjected to a controlled physiological stress treatment. We identified corticosterone-21-HS to be the most sensitive EIA to changes in uGM concentration. To exclude a sex bias, we confirmed the assay’s applicability with samples collected from similar stress treatments in two juvenile males. We used the identified EIA to measure uGM in wild breeding pairs and tested effects of disturbance. Breeding pairs nesting closer to roads and paths had higher uGM concentrations (p = 0.02), which is likely an effect of human recreational activity and disturbance. There was no difference in uGM concentrations between failed and successful nests. Our results highlight the potential impact of road and path proximity on white-tailed sea eagles, with potential importance for species management and conservation, particularly with respect to nest protection zone legislation.

Top-down effects of repatriating bald eagles hinder jointly recovering competitors.

The recovery of piscivorous birds around the world is touted as one of the great conservation successes of the 21st century, but for some species, this success was short-lived. Bald eagles, ospreys and great blue herons began repatriating Voyageurs National Park, USA, in the mid-20th century. However, after 1990, only eagles continued their recovery, while osprey and heron recovery failed for unknown reasons. We aimed to evaluate whether top-down effects of bald eagles and bottom-up effects of inclement weather, habitat quality and fish resources contributed to the failed recovery of ospreys and herons in a protected area. We quantified the relative influence of top-down and bottom-up factors on nest colonization, persistence (i.e., nest reuse) and success for ospreys, and occurrence and size of heronries using 26years (1986-2012) of spatially explicit monitoring data coupled with multi-response hierarchical models and Bayesian variable selection approaches. Bald eagles were previously shown to recover faster due to intensive nest protection and management. Increased numbers of eagles were associated with a reduction in the numbers of osprey nests, their nesting success and heronry size, while higher local densities of nesting eagles deterred heronries nearby. We found little evidence of bottom-up limitations on the failed recovery of herons and ospreys. We present a conservation conundrum: bald eagles are top predators and a flagship species of conservation that have benefited from intensive protection, but this likely hindered the recovery of ospreys and herons. Returning top predators, or rewilding, is widely promoted as a conservation strategy for top-down ecosystem recovery, but managing top predators in isolation of jointly recovering species can halt or reverse ecosystem recovery. Previous studies warn of the potential consequences of ignoring biotic interactions amongst recovering species, but we go further by quantifying how these interactions contributed to failed recoveries via impacts on the nesting demography of jointly recovering species. Multi-species management is paramount to realizing the ecosystem benefits of top predator recovery.

Ontogenetic shifts in the nesting behaviour of female crocodiles.

Body size and age are crucial factors influencing reproductive capacity and success. As females grow, their reproductive investment and success often increase due to improved overall physiological condition and experience gained through successive reproductive events. While much of this work has been conducted on birds and mammals, surprisingly little is known on how body size affects nesting decisions in other long-lived vertebrates. We monitored the movements and nesting behaviour of 57 wild female estuarine crocodiles Crocodylus porosus over a 10-year period (and across consecutive nesting seasons) using externally mounted satellite tags, implanted acoustic transmitters and a network of submerged acoustic receivers. Applying Hidden Markov models to the telemetry-derived location data revealed that female nesting behaviours could be split into three distinct states: (i) ranging movements within home ranges and at nesting sites; (ii) migrations to and from nesting sites; (iii) and nesting/nest guarding. We found that during migration events, larger females migrated further and remained away from dry season territories for longer periods than smaller individuals. Furthermore, not only were migratory movements stimulated by increases in rainfall, larger females migrated to nest sites at lower rainfall thresholds than smaller females. We provide some of the first evidence of body size influencing nesting decisions in an ectothermic vertebrate, with shifts likely resulting from an increased willingness to invest in nest protection among larger and more experienced females.

Polyandrous bee provides extended offspring care biparentally as an alternative to monandry based eusociality

Parental care behavior evolves to increase the survival of offspring. When offspring care becomes complicated for ecological reasons, cooperation of multiple individuals can be beneficial. There are two types of cooperative care: biparental care and worker (helper)-based care (e.g., eusociality). Although biparental care is common in several groups of vertebrates, it is generally rare in arthropods. Conversely, eusociality is widespread in insects, especially the aculeate Hymenoptera. Here, we present a case of biparental care in bees, in Ceratina nigrolabiata (Apidae, Xylocopinae). Similar to eusocial behavior, biparental care leads to greater brood protection in this species. Male guarding increases provisioning of nests because females are liberated from the tradeoff between provisioning and nest protection. The main benefit of parental care for males should be increased paternity. Interestingly though, we found that paternity of offspring by guard males is extraordinarily low (10% of offspring). Generally, we found that nests were not guarded by the same male for the whole provisioning season, meaning that males arrive to nests as stepfathers. However, we show that long-term guarding performed by a single male does increase paternity. We suggest that the multiple-mating strategy of these bees increased the amount of time for interactions between the sexes, and this longer period of potential interaction supported the origin of biparental care. Eusociality based on monandry was thought to be the main type of extended brood protection in bees. We show that biparental care based on polyandry provides an interesting evolutionary alternative.

ХРЕБЕТНІ ТВАРИНИ УРОЧИЩА "ФЕОФАНІЯ"

he local landscape Feofaniya is located on the outskirts of the Kyiv and represents communities of native oak wood with high density of ancient trees and hornbeam forest, steppe meadow, culture phytocenoses, cascade of ponds, stream. For the period 2012-2018 11 species of fish, 8 amphibians, 7 reptiles, 111 birds, 29 mammals were identified. Of these, 82.0 % of species are protected internationally, 8.9 % at the state level of the Ukraine, 12.6 % are regionally rare. In 81% of animal species, the reproductive site passes through the tract, and in half of them the whole life cycle. 19 % of the species composition of birds (Aves) are sedentary, 58 % arrive for nesting, 12 % for feeding, 9 % for wintering, 2 % for migratory (Regulus ignicapillus, Nucifraga caryocatactes). 82.8 % of mammals (Mammalia) are sedentary, 10.3 % are migratory (Pipistrellus nathusii, Pipistrellus pygmaeu, Nyctalus leisleri), 6.9 % with unexplained status (Neovison vison, Capreolus capreolus). The local landscape has 12 alien species. Carassius gibelio, Ctenopharyngodon idella, Hypophthalmichthys molitrix released into ponds with the purpose of stocking. Trachemys seripta elegans bring vacationers to the ponds. Pseudorasbora parva, Perccottus glenii, Streptopelia decaocto, Dendrocopos syriacus, Phoenicurus ochruros, Serinus serinus, Ondatra zibet, Pipistrellus kuhlii, Neovison vison penetrated the local landscape independently from neighboring biotopes. Thanks to biotechnical measures aimed at improving the living conditions of animals (protection of natural nests and the creation of artificial ones), hanging feeders in the winter, hanging shelters for daytime and wintering bats. The negative impact on the biotopes of Feofaniya from the side of recreants is somewhat leveled at the expense of educational work with vacationers. The most relevant propaganda work is aimed at educating correct behavior in nature, explaining the need to protect all plant and animal species, their biotopes, and explaining the consequences of disturbing the balance of sustainable development of ecosystems.

Montagu\u2019s Harrier breeding parameters in relation to weather, colony size and nest protection schemes: a long-term study in Extremadura, Spain

On the basis of long-term (2001–2017) and extensive data (> 1700 breeding attempts), we assess factors influencing breeding parameters in Montagu’s Harrier (Circus pygargus), a medium-sized ground-nesting semi-colonial raptor breeding in cereal fields, in a study area in its core distribution range (Extremadura, Spain). We evaluated annual and long-term variation in breeding parameters, as well as changes in environmental variables such as weather or harvest date. We then evaluated breeding failure and productivity in relation to nest protection measures, weather conditions, lay date and colony size. We found a significant trend for productivity to decrease over the 17-year study period, associated with a trend for predation probability to increase over time. Harvest occurred increasingly earlier in more recent years. The success rate of nests protected with unfenced unharvested patches (the most frequently used protection measure) increased with harvest date, but also declined throughout the study period for equivalent harvest dates. When considering all explanatory variables together, probability of nest success decreased significantly with lay date and throughout the study period, increased with annual rainfall and varied in relation to protective measures (being highest for nests protected with fences or where harvest in the plot had been delayed). In addition, among successful nests, fledged brood size also decreased significantly with lay date and temperature, and increased with annual rainfall. We found no effect of number of neighbours on breeding output. We discuss our results in relation to future conservation prospects for the species.

Nesting association of swifts (Apodidae) and wasps in Brazil

Associations between social insects, such as wasps and bees, and birds are a common strategy related to nest protection. Several examples exist in the literature of bird–wasp interactions, many in the Neotropics, but some bird families, including swifts (Apodidae), lack information regarding this kind of association. This work reports 2 cases of Neotropical swift species nesting adjacent to wasp nests in southeastern Brazil: the Sooty Swift (Cypseloides fumigatus) and Lesser Swallow-tailed Swift (Panyptila cayennensis). These are the first records of this kind of association in Brazil.

Behavioural modification of a social spider by a parasitoid wasp

1. Manipulation of host behaviour by parasitoids has long captured the imagination of ecologists. Parasitoid wasps in the Polysphincta group of genera develop as external parasitoids of spiders.2. In the present study, the previously undescribed interaction between a Zatypota sp. wasp (Ichneumonidae) and a social spider Anelosimus eximius (Theridiidae) is described. The larva of this Zatypota wasp is found to induce its host to disperse from their communal web and build an entirely enclosed web consisting of densely spun silk.3. The wasp is observed to target primarily immature A. eximius individuals, with 37.5–44% of nests in a given area being parasitised. Of those nests, approximately 1.3–2.0% of individuals are hosts to the parasitoid larvae. Larger spider colonies had a significantly higher probability of harbouring parasitoids.4. This interaction results in unusual behaviours for A. eximius induced by the parasitoid: (i) leaving the protection of the social nest and (ii) building a unique, altered web that it would not otherwise build.It is suggested that the wasp may be tapping into ancestral dispersal behaviours in its host and that a social species provides this wasp an evolutionary advantage by allowing a stable host source.

The scent of infanticide risk? Behavioural allocation to current and future reproduction in response to mating opportunity and familiarity with intruder

The killing of young by unrelated males is widespread in the animal kingdom. In short-lived small rodents, females can mate immediately after delivery (post-partum oestrus) and invest in future reproduction, but infanticide may put the nestlings, their current reproductive investment, at risk. Here, we investigated the behavioural trade-offs between mating interest and nest protection in an arena experiment with bank voles (Myodes glareolus). Non-gravid females (n = 33) were housed at one end of a large structured arena with their nestlings. Different scents (cage bedding) were presented to each female in a replicated design. Three combinations of mating opportunities and male-female familiarity were simulated using different scent donors: mating opportunity with the sire of the nestlings with whom the female was familiar; mating opportunity with a male unrelated to the offspring and unfamiliar to the female, thus posing a higher risk to the offspring; and neither risk nor mating opportunity (clean control). Most females investigated male scents, regardless of familiarity, leaving their litter unprotected. During control treatment, females with larger litters spent less time at the scent area, indicating increasing nursing demands or better protection. Females with older litters visited scents more often, suggesting an increased interest in reproduction while they are non-gravid alongside the decreased risk of infanticide for older young. In the presence of unfamiliar scents, females spent more time protecting their nests, supporting the perceived association of unfamiliarity with infanticide risk. Thus, rodent females flexibly allocate time spent between searching for a mate and protecting their nest, which is modulated by their familiarity with a potential intruder.Significance statementInfanticide by conspecific males is an extreme form of sexual conflict and has large costs on females, abolishing their investment into current offspring. In an experimental approach, we exposed lactating female bank voles to different combinations of mating opportunity and familiarity to a (simulated) intruder: (1) the sire of the nestlings with whom the female was familiar and, therefore, potentially less risky in terms of infanticide; (2) a male which was unrelated and unfamiliar to the female and thus posed a higher risk to the offspring; or (3) as a control, cage bedding, which posed neither risk of infanticide nor a mating opportunity. We show that females flexibly allocated pup protection and mating interest based on their familiarity with the male, indicating that the unfamiliar males pose a threat to offspring, which is perceived by the females. Females further adjusted their behaviour to the size and/or age of their current litter, investing more time in male scents when offspring were older, thus balancing future and current investments into reproduction.

Nest sites as a key resource for population persistence: A case study modelling nest occupancy under forestry practices.

Natural nest sites are important breeding resource in terms of population dynamics, especially in forest systems where nest trees limit populations or timber harvesting destroys nests. Nest structures usually have a long life and can be reused by breeding pairs across multiple breeding seasons, so studying their dynamics is of relevance for biodiversity conservation. In this study, we develop a dynamic model to evaluate nest site availability and its influence on the breeding settlement of a forest raptor community composed of booted eagle (Hieraaetus pennatus), common buzzard (Buteo buteo) and northern goshawk (Accipiter gentilis) in a Mediterranean forest ecosystem in southeast Spain. This model approach is also applied to analyse the influence of forestry practices on the dynamics of occupied nests for a simulated period (2010–2050). The simulated scenarios include unmanaged forest and timber harvesting practices of clearcuttings every ten years considering two factors: the age class of trees for clearcutting (40, 50, 60 and 70 years old) and the type of forest management (with or without nest protection). Our simulated results show that the number of breeding pairs is constant during the period without timber harvest, whereas breeding pairs gradually decrease in the scenario of clearcutting trees aged from 70 to 50-years without nest protection, and populations become extinct with the clearcutting of 40-year old trees. Considering the practice of clearcutting and nest protection, nest occupancy can reach the maximum number of occupied nests for the scenarios of cutting 70 and 60-year old trees, and maintain populations without extinction for the scenarios of cutting 40-year old trees. We conclude that nest sites (whether occupied or not) are key resources for increasing the occupancy of the forest raptor community and that nest protection measures buffer the effects of clearcuttings, thus preventing population extinction.

Evaluating the effectiveness of conservation measures for European grassland-breeding waders.

Farmland birds are among the most threatened bird species in Europe, largely as a result of agricultural intensification which has driven widespread biodiversity losses. Breeding waders associated with grassland and arable habitats are particularly vulnerable and a frequent focus of agri‐environment schemes (AES) designed to halt and reverse population declines. We review existing literature, providing a quantitative assessment of the effectiveness of policy and management interventions used throughout Europe to improve population and demographic metrics of grassland‐breeding waders. Targeted AES and site protection measures were more likely to be effective than less targeted AES and were ten times more likely to be effective than would be expected by chance, particularly for population trend and productivity metrics. Positive effects of AES and site protection did not appear synergistic. Management interventions which had the greatest chance of increasing population growth or productivity included modification of mowing regimes, increasing wet conditions, and the use of nest protection. Success rates varied according to the species and metric being evaluated. None of the policy or management interventions we evaluated were associated with a significant risk of negative impacts on breeding waders. Our findings support the use of agri‐environment schemes, site protection, and management measures for grassland‐breeding wader conservation in Europe. Due to publication bias, our findings are most applicable to intensively managed agricultural landscapes. More studies are needed to identify measures that increase chick survival. Despite broadly effective conservation measures already in use, grassland‐breeding waders in Europe continue to decline. More research is needed to improve the likelihood and magnitude of positive outcomes, coupled with wider implementation of effective measures to substantially increase favorable land management for these species.

Status, distribution, and nesting ecology of Snapping Turtle (&lt;i&gt;Chelydra serpentina&lt;/i&gt;) on Cape Breton Island, Nova Scotia, Canada

Based on current knowledge of the ecology and distribution of Snapping Turtle (Chelydra serpentina), both in eastern Canada and elsewhere, we conclude this species is native to Cape Breton Island. Seventy-two reports of Snapping Turtle from Cape Breton (1999–2017) indicate a range centred in the area south of Bras d’Or Lake. Date of oviposition ranged from 19 June to 10 July (median = 26 June) among 26 nests observed during 2012–2014. Clutch size for these nests was 23–65 eggs (mean = 46) and among 25 protected nests average rate of hatchling emergence was 21.5%. Time from oviposition to emergence of hatchlings (n = 256) was 75–120 days (mean = 87.2; SD = 9.0) among 20 nests. First emergence ranged from 9 September to 20 October (75–114 nest days; mean = 90) and last emergence ranged from 13 September to 28 October (86–120 nest days; mean = 100). Duration of emergence ranged from one day (i.e., synchronous emergence; five nests) to 37 days (mean = 11 days). The number of days on which hatchlings emerged at a nest ranged from one to nine days (mean = 4 days). Maximum carapace length was 25.0–31.8 mm (mean = 29.0 mm) and maximum carapace width was 23.5–30.0 mm (mean = 27.0 mm) for 256 hatchlings that emerged from 20 protected nests. Mass of hatchlings was 4.9–9.9 g (mean = 7.8 g).

Investigating parental care behaviour in same-sex pairing of zoo greater flamingo (Phoenicopterus roseus).

Same-sex pair bonds have been documented in several animal species and they are widespread in birds. However, little is known about the evolutionary origin and the adaptive value of such behaviour. The aim of this study was to investigate the parental behaviour of four zoo female greater flamingos involved in two breeding pairs, housed in a flock at Parco Natura Viva, Italy. Further, the behaviour of the study females was compared with that of male and female flamingos in heterosexual pairs described in a previous published work on this same flock. For each pair, the behaviour of both birds during the incubation period was recorded and twenty 10-minute sessions were run within the incubation period. A continuous focal animal sampling method was used to collect data on location (on the nest or not on the nest) and the parental care behaviour (e.g.: agonistic behaviours toward disturbing conspecifics, egg-care, nest-building, self-comfort behaviour, sleeping) of the two pairs. Data of the current study females were compared with those of females and males involved in heterosexual pairs of this same flock. Results showed that within each pair the egg-layer female stayed away from the nest more than the other female. In addition, the female that did not lay an egg was more involved in agonistic behaviour compared to other females, particularly when in specific locations. In heterosexual pairs, male flamingos were more involved in the incubation and in nest protection. Moreover, no significant differences in the time spent on the nest and away from the nest between the heterosexual male and the non-layer females of same-sex pairs were found. The same findings were reported when comparing heterosexual females and the egg-layer females of the same-sex pairs. Therefore, our findings suggest that in greater flamingos the behaviour of the female–female pairs seems to be equivalent to that of male-female bonds. Such research provides more insight into flamingo social behaviour, and their reproductive cycle, and provides information on why pair bonds may form and how these affect the wider breeding behaviour of the flock.

Juvenile Burrowing Owl Nighttime Space-Use In Southern New Mexico

In some areas, Burrowing Owls (Athene cunicularia) occur in human-altered, urbanized environments. However, their use of these anthropogenic land-cover types during nighttime is not well understood. We studied nocturnal and crepuscular space-use of eight juvenile Burrowing Owls in urban, greenspace, and agriculture dominated landscapes during 2012 and 2013 in Dona Ana County, New Mexico. For each owl, we obtained an average of 22 (range 14–37) nighttime telemetry fixes covering a period of 1–8.5 wk post-fledging. The juvenile Burrowing Owls avoided urban cover types and spent more time in agriculture and greenspace. In agricultural areas, owls used canals, weedy ditches, and associated farm roads, whereas in greenspace owls used city parks, golf courses, and patches of native habitat. Juvenile owls in this study were not observed to move large distances and on average most owls (n = 5) remained within 500 m of their roost burrow, with one owl traveling up to 743 m from its roost site. Conservation efforts for Burrowing Owls within human-altered environments should focus on the protection of nest and roost burrows near important foraging areas.

Phenotypic integration in an extended phenotype: among-individual variation in nest-building traits of the alfalfa leafcutting bee (Megachile rotundata).

Structures such as nests and burrows are an essential component of many organisms' life-cycle and require a complex sequence of behaviours. Because behaviours can vary consistently among individuals and be correlated with one another, we hypothesized that these structures would (1) show evidence of among-individual variation, (2) be organized into distinct functional modules and (3) show evidence of trade-offs among functional modules due to limits on energy budgets. We tested these hypotheses using the alfalfa leafcutting bee, Megachile rotundata, a solitary bee and important crop pollinator. Megachile rotundata constructs complex nests by gathering leaf materials to form a linear series of cells in pre-existing cavities. In this study, we examined variation in the following nest construction traits: reproduction (number of cells per nest and nest length), nest protection (cap length and number of leaves per cap), cell construction (cell size and number of leaves per cell) and cell provisioning (cell mass) from 60 nests. We found a general decline in investment in cell construction and provisioning with each new cell built. In addition, we found evidence for both repeatability and plasticity in cell provisioning with little evidence for trade-offs among traits. Instead, most traits were positively, albeit weakly, correlated (r~0.15), and traits were loosely organized into covarying modules. Our results show that individual differences in nest construction are detectable at a level similar to that of other behavioural traits and that these traits are only weakly integrated. This suggests that nest components are capable of independent evolutionary trajectories.