Determining habitat quality for the cooperatively breeding Rufous Treecreeper,Climacteris rufa

Abstract The theory of habitat selection predicts that organisms should use habitat that maximizes their fitness. The cooperatively breeding Rufous Treecreeper, Climacteris rufa, exhibits non‐random habitat use at a number of spatial scales. By assessing correlative relationships between nest‐site use and nest success, and territory use and reproductive success and survival, it was determined whether non‐random use of habitat yields fitness benefits. It was also determined whether breeding group size contributed significantly to fitness once differences in territory quality had been considered. Structural characteristics of nest sites that were positively correlated with the probability of a site being used had no relationship with nest success. This result probably reflects the relatively unrestricted access to an abundance of suitable nest sites in the study area. Habitat traits that predicted territory use by treecreepers were positively correlated with a number of fitness measures. They were also positively correlated with breeding group size and provisioning rate to nestlings, which in turn were correlated with fitness. However, group size was not significantly related to any measure of fitness, except primary male survival, once territory quality had been considered. The quality of territories occupied by Rufous Treecreepers appeared to be a significant factor for breeding group fitness.     

Family status and contributions to breeding by Florida scrub jays

Nestling care by Florida scrub jay Aphelocoma c. coerulescens breeders and helpers is quantified. Breeding males and older male helpers deliver more food than first-year helpers and older female helpers. Breeding males adjust the quantity of food they deliver inversely to that delivered by their helpers. Older female helpers, who make many nest visits without delivering food, attempt to usurp the nest-sitting role of the breeding female. The advantages of group breeding to the breeders seem clear. Pairs with helpers live longer and produce more fledglings. The advantages of being a helper, though obscure, probably include non-altruistic factors such as increased survival and, for males, increased chances of obtaining space for breeding. Food contributions of helpers seem to parallel these opportunities.     

Group composition affects male reproductive partitioning in a cooperatively breeding cichlid

Individuals within groups of cooperatively breeding species may partition reproduction, with the dominant pair often taking the largest share. The dominant's ability to reproductively control subordinates may depend on differences in competitive ability, due to, e.g. body size differences, but may also depend on the number of same‐sex competitors inside the group. We tested experimentally whether subordinates reproduce more when these subordinates are large or when a second subordinate of the same sex need to be controlled by the dominants, using the cooperatively breeding cichlid Neolamprologus pulcher. Dominant pairs were assisted by a large and a small unrelated subordinate; sexes of these fish were varied in a full‐factorial design (giving four treatments). Dominant males lost significantly more parentage to the large subordinate male when a small subordinate male was also present, compared to when a small subordinate female was present. However, subordinate paternity was generally low and did not significantly curb total dominant male reproductive output, which was more affected by the sizes and numbers of reproductive females present inside his group. Dominant female maternity, clutch sizes and total output did not depend on the treatments. Subordinate–subordinate reproduction was virtually absent (one out of 874 offspring). Female subordinates were more likely to provide care for their own broods. In contrast, male subordinates did not adjust their level of care to their parentage. Variability in female subordinate alloparental brood care was particularly high, with females showing more care than males in general. We also detected effects of growth rate and food ration on parentage independent of the treatments, most notably: (i) a trade‐off between dominant male growth rate and paternity; (ii) a decrease in dominant male paternity with increasing food ration; (iii) a positive effect of growth rate on paternity in small males. We conclude that dominant males should be sensitive to the number and sizes of subordinate males present in their group, particularly when these subordinates are not helpful or grow fast, and food is plentiful. Dominant females should be less sensitive, because female subordinates do not appear to impose reproductive costs and can be helpful through alloparental brood care.     

Double-nesting behaviour and sexual differences in breeding success in wild Red-legged Partridges Alectoris rufa

Double-nesting behaviour, a rare breeding system in which females lay in two nests, one incubated by herself and the other one by her mate, could be considered an intermediate stage in the evolutionary trend from biparental to uniparental care of single clutches. We examined the occurrence and success of double-nesting behaviour in Red-legged Partridges Alectoris rufa in Central Spain. Clutch size and hatching success were recorded, as well as the variation in these between years and between incubating sexes. Participation in incubation was higher for females (94.76%) than males (41.0%), and the proportion of incubating males varied markedly between years, with no incubating males in one dry year and approximately 50% of males incubating in other years. There was significant variation among years and between sexes in laying date, clutch size and hatching success. Clutch size decreased with later laying date in males and females. The probability of clutch loss to predation differed between sexes, being much higher for nests incubated by females. Our results suggest that both rainfall and predation influence the occurrence and success of double-nesting.     

Notes on the breeding biology of Rufous Potoos (Nyctibius bracteatus) in lowland Ecuadorian Amazon

Five species of potoos occur in Ecuador, with Rufous Potoos (Nyctibius bracteatus) being one of the least known. We monitored a nest site of Rufous Potoos in a lowland forest in the Ecuadorian Amazon and provide information about the behavior of a nestling and one or more adults. Observations were conducted opportunistically from 10 August to 10 September 2018, and an infrared heat‐and‐motion activated camera was used to monitor the nest site from 11 September to 13 November 2018. We recorded 2006 10‐s videos of the nestling and/or adult(s) that we used to quantify behavior. The nestling spent most of its time perching (53%) and stretching (20.7%). Beginning when ~ 23 d old, the nestling began exercising its flight muscles and did so with increasing frequency over time. Adult behaviors included perching while brooding the nestling (55%), stretching (24%), flying (10.4%), and feeding the nestling (10.4%). The duration of the nestling period, ~ 2 mo, in our study was similar to that reported previously for this species. Our observations suggest that the breeding and nestling behavior of Rufous Potoos is similar to that of other Nyctibius species. However, additional studies are needed to better document the behavior of Rufous Potoos during the incubation period.     

Resource value affects territorial defense by Broad-tailed and Rufous hummingbirds

ABSTRACT.   Territorial behavior of Broad-tailed ( Selasphorous platycercus ) and Rufous ( Selasphorous rufus ) hummingbirds in Colorado was measured at sites with feeders containing10%, 20%, and 30% sucrose solutions, respectively. The presence or absence of territory holders, number of intruders, and intensity of defense were measured at the three levels of energy availability. Migrating Rufous Hummingbirds displaced Broad-tailed Hummingbirds from territories they had defended during the breeding season; Broad-tailed Hummingbirds then defended only lower quality sites. Both Broad-tailed and Rufous hummingbirds employed more energetically expensive behaviors when defending high quality sites, with longer chases more often supplemented with chip calls and hovering. Other investigators have suggested that chip calls and hovering are precursors to a chase. However, I found that chasing was the default response to the presence of an intruder. Chip calls and hovering were added to intensify a chase. In the few cases where chip calls were uttered or hovering occurred without a chase, Rufous Hummingbirds were more likely to exhibit this behavior than Broad-tailed Hummingbirds.     

The Madagascar Fauna and Flora Group as an example of how a consortium is enabling diverse zoological and botanical gardens to contribute to biodiversity conservation in Madagascar

Using the example of Madagascar Fauna and Flora Group (MFG), we look at the factors which contribute to the successful maintenance of an international consortium dedicated to the conservation of Malagasy biodiversity. We discuss the philosophy, mission and set-up of the MFG and how, over its 25-year history, it has enabled the productive collaboration of its diverse international members to achieve the common goal of helping to protect Madagascar's unique biodiversity. We explore the benefits of pooling resources to fund a stable base of personnel and infrastructure to maximise the conservation impact of contributions from organisations that might not otherwise be able to fund viable independent programmes and consider the benefits that accrue to partners in the consortium. We highlight specific examples of plant conservation projects set up as a result of the productive working relationship between MFG and Missouri Botanical Garden to reinforce the argument that like-minded organisations working in successful partnership can far exceed the conservation capacity of individual institutions.     

The relative contributions of species richness and species composition to ecosystem functioning

How species diversity influences ecosystem functioning has been the subject of many experiments and remains a key question for ecology and conservation biology. However, the fact that diversity cannot be manipulated without affecting species composition makes this quest methodologically challenging. Here, we evaluate the relative importance of diversity and of composition on biomass production, by using partial Mantel tests for one variable while controlling for the other. We analyse two datasets, from the Jena (2002–2008) and the Grandcour (2008–2009) Experiments. In both experiments, plots were sown with different numbers of species to unravel mechanisms underlying the relationship between biodiversity and ecosystem functioning (BEF). Contrary to Jena, plots were neither mowed nor weeded in Grandcour, allowing external species to establish. Based on the diversity–ecosystem functioning and competition theories, we tested two predictions: 1) the contribution of composition should increase with time; 2) the contribution of composition should be more important in non‐weeded than in controlled systems. We found support for the second hypothesis, but not for the first. On the contrary, the contribution of species richness became markedly more important few years after the start of the Jena Experiment. This result can be interpreted as suggesting that species complementarity, rather than intraspecific competition, is the driving force in this system. Finally, we explored to what extent the estimated relative importance of both factors varied when measured on different spatial scales of the experiment (in this case, increasing the number of plots included in the analyses). We found a strong effect of scale, suggesting that comparisons between studies, and more generally the extrapolation of results from experiments to natural situations, should be made with caution.     

Variation in contributions to teaching by meerkats

Recent evidence from cooperative insect, bird and mammal societies has challenged the assumption that teaching is restricted to humans. However, little is known about the factors affecting the degree to which individuals in such societies contribute to teaching. Here, I examine variation in contributions to teaching in meerkats, where older group members teach pups to handle difficult prey. I show that investment in teaching varies with characteristics of pups, helpers, groups and ecological conditions. Although prior experience in caring for pups did not significantly influence teaching behaviour, younger helpers, which were still investing in growth, contributed less to teaching than older individuals. This suggests that, in common with other cooperative activities, contributions to teaching vary with the costs experienced by individual group members. However, in contrast to other forms of helping in meerkats, I detected no effects of nutritional state on teaching, suggesting that it carries relatively low costs. In species where individuals can potentially gain direct or indirect fitness benefits from facilitating learning in others, low costs divided among multiple group members may help tip the balance towards selection for teaching.     

The composition and foraging behaviour of mixed-species flocks of forest-living birds in Madagascar

Mixed-species flocks of forest living birds were investigated in a rainforest at Perinet/ Analamazaotra (Andasibe), Madagascar. Most insectivorous birds in the area participated in mixed-species flocks. Flocks were composed of foliage gleaners, foliage-branch gleaners, trunk gleaners and flycatchers. Species whose foraging techniques and foraging locations in vegetation were similar were different from each other in foraging heights. The nuclear species often occurred in small conspecific flocks in and out of mixed-species flocks.     

First nest description, breeding behaviour and distribution of the Madagascar Serpent-Eagle Eutriorchis astur

The critically endangered, endemic Madagascar Serpent-Eagle Eutriochis astur was searched for and studied from 1993-98 on Masoala Peninsula, northeastern Madagascar. Fifteen individual serpent-eagles were detected at nine different localities throughout the Masoala Peninsula. The first nest of the Madagascar Serpent-Eagle was discovered on 7 November 1997. The nest was in an epiphytic fern Asplenium nidus supported by vines and branches, 20.1 m above the ground in a Potameia capuroni of 36.2 cm diameter at breast height. The epiphytic fern was lined with leaves in the centre and twigs were positioned to form a nest rim. The nest measured 76 times 57 cm and contained one white egg. The female and male incubated for 77% and 21% of 118 hours of nest observations, respectively. The egg hatched on 21 November 1997, and the young fledged 62 days later on 22 January. Chameleons Furcifer and Calumma spp., and leaf-tailed geckos Uroplatus sp., made up the most numerous prey types taken, representing 83% of the 133 identified prey. Currently, the Masoala Peninsula forest contains the greatest number of sightings and known density of serpent-eagles in Madagascar.     

Four New Species of the Feather Mite Genus Vanginyssus Mironov, 2001 (Astigmata: Pteronyssidae) from the Vangas (Passeriformes: Vangidae) in Madagascar

Four new feather mite species of Vanginyssus Mironov, 2001 are described from vangas (Passeriformes: Vangidae), an endemic passerine family from Madagascar: Vanginyssus euryceros n. sp. from the helmet vanga Euryceros prevostii Lesson, V. madagascarinus n. sp. from the blue vanga Cyanolanius madagascarinus (Linnaeus), V. mystacornis n. sp. from the Crossley’s babbler Mystacornis crossleyi (Grandidier) and V.␣orioliae n. sp. from the Bernier’s vanga Oriolia bernieri Geoffroy Saint-Hilaire. A key to the five known species of Vanginyssus is provided.     

Variable infant care contributions in cooperatively breeding groups of wild saddleback tamarins

Among non-human primates, alloparental infant care is most extensive in callitrichines, and is thought to be particularly costly for tamarins whose helpers may suffer increased energy expenditure, weight loss, and reduced feeding time and mobility. The costs and benefits of infant care likely vary among group members yet very few wild studies have investigated variable infant care contributions. We studied infant care over an 8-month period in four wild groups of saddleback tamarins in Bolivia to evaluate: (a) what forms of infant care are provided, by whom, and when, (b) how individuals adjust their behavior (activity, vigilance, height) while caring for infants, and (c) whether individuals differ in their infant care contributions. We found that infant carrying, food sharing, and grooming varied among groups, and immigrant males—those who joined the group after infants were conceived—participated less in infant care compared to resident males. Adult tamarins fed less, rested more, and increased vigilance while carrying infants. Although we did not detect changes in overall activity budgets between prepartum and postpartum periods, tamarins spent more time scanning their environments postpartum, potentially reflecting increased predation risk to both carriers and infants during this period. Our study provides the first quantitative data on the timing and amount of infant carrying, grooming, and food transfer contributed by all individuals within and among multiple wild groups, filling a critical knowledge gap about the factors affecting infant care, and highlighting evolutionary hypotheses for cooperative breeding in tamarins.