Distribution and characteristics of the Makassar tarsius Tarsius fuscus fischer, 1804 sleeping nest in the tropical primary and secondary forests of South Sulawesi

Tarsius fuscus, whose distribution is limited to the southern part of South Sulawesi, Indonesia, is threatened by poaching and habitat loss, with the latter leading to the disappearance of its sleeping nest locations, despite the species’ wide range of habitat requirements. This study aimed to identify the distribution and characteristics of T. fuscus sleeping nests. Research took place in Bantimurung Bulusaraung National Park primary and secondary forest areas and Hasanuddin University Educational Forest. Sleeping nest locations were identified through vocalizations in the morning (4.30–6.00 am) and direct visual observations. Sleeping nest distribution maps were created using QGIS 3.16. Sleeping nests were found in karst rock shelters, Ficus trees, forest pandanus, and fallen tree debris, at elevations of 68–947 mdpl, 4–42° slopes, temperatures ranging 23.3–29.1°C, and distances to roads and settlements of 21.4–460.3 m and 325.9–1888.5 m, respectively. Tarsius fuscus tended to nest in primary forest rather than secondary forest, although this may also be caused by the larger proportion of primary forest. Protecting both primary and secondary forest is crucial, but particular focus should be given to the latter, owing to its susceptibility to human disturbance.

The Sub-Lethal and Density-Dependent Effects of an Invasive Wasp on an Endemic Ant

<p><b>The detrimental effects of invasive species on recipient taxa are most frequently reported in terms of displacement or extinction. However, there may be other less obvious effects. For example, a reduction in resource availability mediated by a novel competitor may affect growth and development in recipient species. The cost of aggressive competitive interactions with invasives may promote niche shifts or altered spatial distribution to minimise competition, and intense predation by exotic species may result in a reduced effective population size with a concomitant reduction in genetic diversity. In this thesis I examined the sub-lethal effects of varying densities of the invasive competitor and predator Vespula vulgaris on the morphology, behaviour, population genetics and spatial distribution of the New Zealand endemic ant Prolasius advenus.</b></p> <p>The restriction of food resources can result in reduced worker size and altered scaling relationships of adult body parts in ants. Measurements of nine morphological characters from P. advenus worker ants collected from sites of varying wasp density revealed that workers were significantly smaller where there were more wasps. I also found evidence of allometric scaling relationships among body parts, which varied between areas of high and low wasp density. In particular the scaling relationships between the abdominal segments and overall size were found to be weaker where there were more wasps. This scaling variation resulted in ant workers with proportionally smaller abdomens in areas where wasps were most abundant, which might reduce their resource gathering and defensive efficiency.</p> <p>I tested the hypothesis that tasks performed by workers would be size correlated. In the presence of high densities of wasps, honeydew collection and brood care was undertaken by larger workers, whereas foraging in leaf litter was undertaken by smaller workers. In contrast, no relationship was found between task and worker size where wasp densities were lower. I suggest that in addition to increased efficiency in the collection of liquid carbohydrate resources larger workers may also serve a defensive role. I also tested the hypothesis that where the exclusively diurnal wasps were most abundant P. advenus workers would minimise potential competitive interactions by foraging predominantly at night. However, P. advenus were found to forage as much or more by day in the presence of high densities of wasps and to forage more nocturnally where wasps were sparse. Increasing the number of foragers by day may improve P. advenus’ competitive ability with wasps, but has the potential to come at the cost of other nest functions, energetic gains and increased worker mortality. Competitive mechanisms might influence ant population genetics, but wasps have also been shown to prey on dispersing ant queens. Analysis of microsatellite DNA markers revealed evidence of a genetic bottleneck in P. advenus populations where invasive predatory wasps have persisted at high population densities for more than twenty years. Ant populations at all wasp densities displayed significant heterozygote deficit, which may indicate that even at comparatively low densities predation by wasps has a detrimental effect on P. advenus genetic diversity. Alternatively, the observed heterozygote deficit may be the result of limited dispersal, population substructure or the peculiarities of the ant species‟ mating system. An examination of the broader population genetic structure of P. advenus from the seven sites sampled indicated that they were derived from two distinct populations. However, no individual assigned entirely to either population suggesting either some remaining admixture between the two populations or that they are derived from a common ancestral population.</p> <p>Finally I examined the effects of increasing wasp density, honeydew availability and habitat diversity on the distribution of P. advenus. Prolasius advenus nests tended to be smaller and populations displayed less variation in nest size where wasp densities were highest, which could indicate reduced longevity. Nest distribution was overdispersed relative to both con-and hetero-specific neighbours in high wasp density sites, but apparently randomly distributed in low wasp density sites. Both wasp and ant nest densities were greatest where honeydew was most abundant and plant diversity was lowest. These results suggest that intra- and inter-specific competition in combination with resource and nest site availability influences P. advenus nest distribution.</p> <p>Competition and predation by invasive species may influence recipient species‟ morphology, behaviour, genetic diversity and spatial distribution over a comparatively short period of time. These effects are much more subtle than under situations of direct predation. Such effects may not be immediately obvious in terms of abundance, but have potential long-term implications for the fitness and persistence of P. advenus in the presence of high densities of wasps.</p>

The Sub-Lethal and Density-Dependent Effects of an Invasive Wasp on an Endemic Ant

<p><b>The detrimental effects of invasive species on recipient taxa are most frequently reported in terms of displacement or extinction. However, there may be other less obvious effects. For example, a reduction in resource availability mediated by a novel competitor may affect growth and development in recipient species. The cost of aggressive competitive interactions with invasives may promote niche shifts or altered spatial distribution to minimise competition, and intense predation by exotic species may result in a reduced effective population size with a concomitant reduction in genetic diversity. In this thesis I examined the sub-lethal effects of varying densities of the invasive competitor and predator Vespula vulgaris on the morphology, behaviour, population genetics and spatial distribution of the New Zealand endemic ant Prolasius advenus.</b></p> <p>The restriction of food resources can result in reduced worker size and altered scaling relationships of adult body parts in ants. Measurements of nine morphological characters from P. advenus worker ants collected from sites of varying wasp density revealed that workers were significantly smaller where there were more wasps. I also found evidence of allometric scaling relationships among body parts, which varied between areas of high and low wasp density. In particular the scaling relationships between the abdominal segments and overall size were found to be weaker where there were more wasps. This scaling variation resulted in ant workers with proportionally smaller abdomens in areas where wasps were most abundant, which might reduce their resource gathering and defensive efficiency.</p> <p>I tested the hypothesis that tasks performed by workers would be size correlated. In the presence of high densities of wasps, honeydew collection and brood care was undertaken by larger workers, whereas foraging in leaf litter was undertaken by smaller workers. In contrast, no relationship was found between task and worker size where wasp densities were lower. I suggest that in addition to increased efficiency in the collection of liquid carbohydrate resources larger workers may also serve a defensive role. I also tested the hypothesis that where the exclusively diurnal wasps were most abundant P. advenus workers would minimise potential competitive interactions by foraging predominantly at night. However, P. advenus were found to forage as much or more by day in the presence of high densities of wasps and to forage more nocturnally where wasps were sparse. Increasing the number of foragers by day may improve P. advenus’ competitive ability with wasps, but has the potential to come at the cost of other nest functions, energetic gains and increased worker mortality. Competitive mechanisms might influence ant population genetics, but wasps have also been shown to prey on dispersing ant queens. Analysis of microsatellite DNA markers revealed evidence of a genetic bottleneck in P. advenus populations where invasive predatory wasps have persisted at high population densities for more than twenty years. Ant populations at all wasp densities displayed significant heterozygote deficit, which may indicate that even at comparatively low densities predation by wasps has a detrimental effect on P. advenus genetic diversity. Alternatively, the observed heterozygote deficit may be the result of limited dispersal, population substructure or the peculiarities of the ant species‟ mating system. An examination of the broader population genetic structure of P. advenus from the seven sites sampled indicated that they were derived from two distinct populations. However, no individual assigned entirely to either population suggesting either some remaining admixture between the two populations or that they are derived from a common ancestral population.</p> <p>Finally I examined the effects of increasing wasp density, honeydew availability and habitat diversity on the distribution of P. advenus. Prolasius advenus nests tended to be smaller and populations displayed less variation in nest size where wasp densities were highest, which could indicate reduced longevity. Nest distribution was overdispersed relative to both con-and hetero-specific neighbours in high wasp density sites, but apparently randomly distributed in low wasp density sites. Both wasp and ant nest densities were greatest where honeydew was most abundant and plant diversity was lowest. These results suggest that intra- and inter-specific competition in combination with resource and nest site availability influences P. advenus nest distribution.</p> <p>Competition and predation by invasive species may influence recipient species‟ morphology, behaviour, genetic diversity and spatial distribution over a comparatively short period of time. These effects are much more subtle than under situations of direct predation. Such effects may not be immediately obvious in terms of abundance, but have potential long-term implications for the fitness and persistence of P. advenus in the presence of high densities of wasps.</p>

Nest Distribution of Four Priority Raptor Species In Colorado

ABSTRACT Raptors face threats such as habitat modification, climate change, and environmental pollutants in many parts of the western USA, where rapid human population growth exacerbates such pressures. However, information about distribution of raptor nests at broad spatial scales that could inform conservation efforts is lacking. To provide a contemporary estimate of nest distribution of four raptor species of special conservation concern (Bald Eagle [Haliaeetus leucocephalus], Ferruginous Hawk [Buteo regalis], Golden Eagle [Aquila chrysaetos], and Prairie Falcon [Falco mexicanus]) throughout Colorado, we used a statewide database of raptor nesting locations to inform species distribution models for monitoring and management efforts. We used generalized linear models to identify the relationship between nest locations and explanatory covariates relating to land cover, temperature, topography, and prey distribution. We investigated the effect of different methods for selecting the sample of locations available to raptors, comparing four selection frames: sampling from the observed locations of the target-group (i.e., other raptor nests), sampling from within a spatial buffer around observed locations, sampling from outside of the same buffer, or complete random sampling of the background locations without respect to observations. Out-of-sample validation techniques indicated strong predictive accuracy of our models. Each raptor species was best represented by a different one of the four approaches to sample available locations, refuting our expectation that models accounting for bias would perform better than those that did not. Our findings were consistent with generally understood habitat associations of these species. These models can be used to identify hot spots with high relative probability of use by breeding raptors and to inform future monitoring practices that use a standardized, stratified sampling design.

Natural history notes on worker size, colony size, and nest structure of Azteca muelleri Emery, 1893 (Hymenoptera: Formicidae) in Cecropia glaziovii (Rosales: Urticaceae) from the Atlantic Forest

Mutualistic association between Azteca Forel, 1878 ants and Cecropia Loefl. plants are one of the most studied interactions in Neotropics, however, natural history studies of Azteca species still poorly investigated due to the great effort required to conduct detailed descriptive studies. Here, we describe biological aspects of Azteca muelleri Emery, 1893 nesting in Cecropia glaziovii Snethl. in a fragment of Atlantic Forest, addressing (a) colony size; (b) nest distribution on the tree; and (c) worker and queen morphometrics. We collected two C. glaziovii saplings and counted characteristics of the nests and plants. We randomly selected 140 workers to measure and to determine whether intraspecific polymorphism occurs. Workers, immatures, and mealybugs were present in all hollow internodes of plant, and a queen was found. We found isometric morphological variation in A. muelleri. Our study provides new data to understand the biology of A. muelleri nesting in C. glaziovii, one of the most species-rich genera of arboreal ants known for the neotropics.

Colony size affects breeding density, but not spatial distribution type, in a seabird

The spatial distribution of individuals within populations can result in fine-scale density dependence and affect the social environment that is encountered. As such, it is important to quantify within-population spatial structuring and understand the factors that shape it. In this study, we make use of point process statistics to test whether colony size affects the statistical type of spatial nest distribution produced by common terns (Sterna hirundo) breeding at identical manmade rectangular and homogeneous islands of fixed physical size. Comparing subcolonies of variable density both within and across years, we find that inter-nest distances are smaller at higher local and overall breeding density, but that the spatial distribution type does not vary across the observed densities. This suggests that the birds’ main settlement rules do not depend on density. In our case, analyses of fine-scale density dependence or potential social effects therefore do not need to account for between-individual heterogeneity in settlement decision rules or acceptance of these rules. We urge, however, other studies to similarly test for density dependence of the spatial distribution of individuals before undertaking such “downstream” analyses.

Vegetation analysis and population of tarsier (Tarsius spectrumgurskyae) at Batuputih Nature Tourism Park, North Sulawesi, Indonesia

Arrijani, Rizki M. 2019. Vegetation analysis and population of tarsier (Tarsius spectrumgurskyae) at Batuputih Nature Tourism Park, North Sulawesi, Indonesia. Biodiversitas 20: 530-537. Tangkasi or Tarsius (Tarsius spectrumgurskyae) is a world’s smallest primate, which categorized as an endemic and protected species inhabited Sulawesi Island. Batuputih Nature Tourism Park (Batuputih NTP) at Tangkoko Batuangus Nature Reserve, Bitung City, North Sulawesi, Indonesia is one of the habitats of the primate. The research aimed to characterize the habitats of Tarsius that include physical and vegetation characteristics and to figuring out the nest distribution and estimation of the population of this species. The vegetation data were sampled using a quadrat sampling technique around Tarsius nests. The Tarsius population was estimated along a 2 km transect line with the distance 50 m to the left and right across the line (the total width 100 m (0.1 km). Meanwhile, to calculate population abundance (Overall estimate of population size/abundance) can be obtained by multiplying population densities with the total area of ​​all observations. The result revealed that the vegetation types of Tarsius habitats were dominated by tree species which associated with Liana from the family Araliaceae, among them include Spathodea campanulata, Ailanthus integrifolia, Kleinhovia hospital, Alstonia scholaris, Garuga floribunda, Arenga pinnata, and two sleeping trees without accosiated from the species of Ficus tinctoria and Ficus variegata. Tarsius life in groups with 2-8 individuals per group. The estimation of population density was found that there were 270 individuals/km or 2.7 individuals/ha and their total abundance around 1660 individuals of Tarsius lived in Batuputih NTP.