Roost Trees Research Articles

Sociality influences thermoregulation and roost switching in a forest bat using ephemeral roosts.

In summer, many temperate bat species use daytime torpor, but breeding females do so less to avoid interferences with reproduction. In forest‐roosting bats, deep tree cavities buffer roost microclimate from abrupt temperature oscillations and facilitate thermoregulation. Forest bats also switch roosts frequently, so thermally suitable cavities may be limiting. We tested how barbastelle bats (Barbastella barbastellus), often roosting beneath flaking bark in snags, may thermoregulate successfully despite the unstable microclimate of their preferred cavities. We assessed thermoregulation patterns of bats roosting in trees in a beech forest of central Italy. Although all bats used torpor, females were more often normothermic. Cavities were poorly insulated, but social thermoregulation probably overcomes this problem. A model incorporating the presence of roost mates and group size explained thermoregulation patterns better than others based, respectively, on the location and structural characteristics of tree roosts and cavities, weather, or sex, reproductive or body condition. Homeothermy was recorded for all subjects, including nonreproductive females: This probably ensures availability of a warm roosting environment for nonvolant juveniles. Homeothermy may also represent a lifesaver for bats roosting beneath loose bark, very exposed to predators, because homeothermic bats may react quickly in case of emergency. We also found that barbastelle bats maintain group cohesion when switching roosts: This may accelerate roost occupation at the end of a night, quickly securing a stable microclimate in the newly occupied cavity. Overall, both thermoregulation and roost‐switching patterns were satisfactorily explained as adaptations to a structurally and thermally labile roosting environment.

Roosting Habits of TwoLasiurus borealis(Eastern Red Bat) in the Blue Ridge Mountains of Virginia

Abstract Lasiurus borealis (Eastern Red Bat), long considered a common species, is now experiencing population declines. Most studies of their roosting habits have reported that the species uses mature canopy trees. We radio-tracked 2 adult male Eastern Red Bats to their roost trees in the Blue Ridge Mountains of Virginia in June of 2012. Both bats roosted in a different tree each day, but spent 3–5 days roosting in groups of nearby trees before making larger movements out of the study area. Characteristics of roost trees differed markedly between bats. One bat roosted in Castanea dentata (American Chestnut) and Quercus rubra (Red Oak) saplings in early-successional habitat; the other roosted in mature Quercus spp. (oaks) in closed-canopy forest. Most roost trees and nearby trees were shorter and smaller diameter than those reported in previous studies. Our results suggest Eastern Red Bats have relatively broad roosting habits that include use of both early- and late-successional habitat.

Baseline Capture Rates and Roosting Habits ofMyotis septentrionalis(Northern Long-Eared Bat) Prior to White-Nose Syndrome Detection in the Southern Appalachians

Abstract Myotis septentrionalis (Northern Long-eared Bat) is a federally threatened insectivorous bat facing devastating population declines due to white-nose syndrome (WNS). Our study provides pre-WNS (2009) capture rates and roosting-behavior data for Northern Long-eared Bats in the southern Appalachians. We conducted mist-net surveys at 37 sites and radio-tracked female Northern Long-eared Bats to their day roosts in eastern Tennessee and western North Carolina. We compared tree and plot characteristics for roosts and corresponding random trees using Wilcoxon rank-sum tests. Our 43 survey nights yielded 302 bats of 11 species; Northern Long-eared Bats were the most commonly captured species (n = 97). We located 14 unique roosts for 7 radio-tracked bats; Pinus strobus (White Pine) snags (n = 8) were the most common roost sites. We observed a colony of 72 bats using a White Pine snag as a maternity roost. Roost trees were significantly larger in diameter and had more solar exposure above the roost and wi...

Quantifying relative levels of solar radiation at bat roosts using pyranometers

ABSTRACTAlthough the amount of solar radiation received at roost sites used by bats has been speculated to be a factor driving roost‐site selection and roost switching behavior, few studies have scientifically quantified and recorded it over time. We demonstrated through a field test how silicon‐cell pyranometers, which are commonly connected to dataloggers and used in atmospheric studies to measure solar irradiance on a planar surface, can also be used to measure and record relative solar radiation levels at roost trees used by bats and other wildlife. Using commercially available pyranometers might not be feasible for many wildlife studies because they are expensive; we demonstrate how they can be built relatively simply and inexpensively, and calibrated with a commercial silicon‐cell pyranometer. © 2017 The Wildlife Society.

Roosting selection by red and blue Lory (Eos histrio Muller, 1776) in Karakelang Island North Sulawesi

The Red and blue lory is an endemic parrot species from Talaud Islands, North Sulawesi. The use of existing resources is suspected that occurs of selection including the roosting trees. The research aims to identifying the characteristics of Red and Blue Lory roost tree and determining variables in its selection. We measured 14 variables to identify the characteristics and selection of roost tree. Mann-Whitney test, T-test, Chi-sqare test and Binary Logistic Regression were employed to analyze data. We detected 11 roost trees in study field, there are Gehe (Pometia coriacea Radkl) nine individual, Binsar (Ficus variegata) and Lawean (Sterculia sp) one individual. The Chi-square test identified five variables which related to roost tree selection, i.e; branch-free bole length, canopy diameter, canopy density and the number of trees around the roost tree on diameter 20 - 40 cm and > 41 cm. The Logistic regression analysis detected three variables that gave the most influence on roost tree selection, but branch-free bole length gave the most influence on roost tree selection.

Indiana bats roost in ephemeral, fire-dependent pine snags in the southern Appalachian Mountains, USA

The Indiana bat (Myotis sodalis), a species that is federally endangered in the U.S., is being impacted by white-nose syndrome and habitat loss across much of its range. A better understanding of summer roost ecology of the species will enable us to develop management strategies that promote summer survival for breeding adult females and their pups. We conducted a 5year investigation of Indiana bat roost habitat selection and roosting behavior in a large (>250,000ha) forested area of the southern Appalachian Mountains and compared our results to populations in different landscapes across the species’ range. From May to August 2008–2012, we attached radio transmitters to 50 adult females, 3 juveniles, and 7 adult males captured at sites on the Cherokee and Nantahala national forests and Great Smoky Mountains National Park. We radiotracked bats to 95 roosts and measured characteristics of trees, 0.1ha plots, and landscape attributes for 69 of these roosts and associated random trees. We used an AIC approach to compare 14 candidate conditional logistic regression models. The only plausible model, which carried 95% of total model weights, had 3 important terms. Indiana bats showed strong selection for yellow pine (Pinus subgenus Diploxylon) snags that were significantly taller than random trees and in areas with a greater number of snags within 0.1ha. During this study, tree and stand structure were more important for roost selection than larger scale factors and Indiana bats responded to a pulsed and highly ephemeral resource, dead yellow pines, which were a significant component of the large forest tracts. Roosting behavior differed from what has been observed for Indiana bats in other parts of the eastern U.S.; maternity colonies tended to be smaller (<25 bats, but as large as 75 bats prior to pups being volant) and bats were more nomadic, using each roost tree for only 2–3days on average and rarely for more than one year. The differences we observed in roosting behavior in the southern Appalachians suggest it would be wise to consider the broader landscape context when evaluating the roosting ecology of Indiana bats, as local forest types and disturbance events will affect stand structure and roost tree availability. Stand- and landscape-scale management practices that create or preserve large pine snags, such as prescribed fire, coupled with natural or manmade pulsed disturbances, should aid in the management and recovery of the Indiana bat in this region.

Adaptive response to land-use history and roost selection by Rafinesque’s big-eared bats

Although habitat loss and degradation are major contributors to species declines, some species are able to adapt to changes in land use by selecting different habitats or structures in disturbed areas than they do in more pristine habitats. Bats are particularly vulnerable to changes in land use due to their dependence on specific habitat types and structures. The objective of this study was to determine how selection and use of roost trees, and niche breadth of Rafinesque's big-eared bats (Corynorhinus rafinesquii) varied with land-use history. I examined use and selection of roosts at 3 bottomland hardwood sites that varied in amount and time since timber harvest. Fortynine transects were established as a means of searching for bats in trees with basal cavity openings and were surveyed 2–9 times. Bats at the most-disturbed sites exhibited the broadest niches, using a greater number of tree species and habitat types, although bats at the least-disturbed site used a broader range of cavity volumes. Cavity characteristics were the primary factors governing roost selection by Rafinesque's big-eared bats, but selection varied among sites. Probability of use increased with increasing cavity volume for bats at all sites, but bats at the most-disturbed site primarily used trees in the smallest cavity volume class, whereas bats at the least-disturbed site primarily used trees in the largest cavity volume class. Results of this study suggest that Rafinesque's bigeared bats can adapt to a range of habitat conditions if trees with large cavities are available. However, future studies need to determine the long-term viability of this species in disturbed habitats.

Identification of Sampiri Birds Colonies Roosting Tree Species in Karakelang Island Talaud Islands North Sulawesi

The aims of this study was to identify the species and describe the morpohology of roosting tree used by sampiri colonies. The research was conducted form February to May 2014. Direct observation and recording morphology characteristic of the roosting tree were used as methodology. Data were analyzed descriptively and qualitatively and then displayed in the form of images and tables. There were six sampiri colonies using different roost trees. The roost trees were gehe (Pometia corriacea Radkl), binsar (Ficus variegata Blume), lawean (Sterculia sp.), dominated by gehe.

Habitat Use by the Endemic Malagasy BatHipposideros commersoniin a Littoral Forest

We investigated habitat use by the endemic Malagasy bat Hipposideros commersoni in evergreen littoral rainforest during the wet season in 2006, in order to better inform conservation guidelines. We used radiotracking to locate roosting and foraging sites. Roosts, typically 5.4 ± 0.2 m from the ground, were always occupied by single bats and were found on branches of trees with a diameter at breast height of 8.2 ± 0.7 cm. Home range size was 31.8 ± 9.2 ha for males and 41.7 ± 12.9 ha for females. Roosts were always located within the foraging areas and only five (5.4%) of the 91 located were situated outside the sheltered littoral forest. Foraging bats made greatest use of natural, sheltered littoral forest and relatively few foraging sorties occurred beyond the forest edge. Females were not trapped during January and may undergo local movements at that time. There are no known caves in the vicinity of the study area and H. commersoni roosted only on trees. Previous studies in Madagascar have highlighted the importance of caves for bats and we now extend this to include tree roosts, within the evergreen rainforest.

New records of tree roosts of Noctilio albiventris from the Pantanal, Brazil

ABSTRACTThe selection of roosts is considered a critical factor to the survival of Noctilio albiventris. Thus, we located and identified N. albiventris day roosts in the Pantanal, near the Miranda River. We identified four species of tree: Banara arguta, Inga vera, Ocotea diospyrifolia and Vitex cymosa. Additional studies are important to understand the impact of specific requirements in the selection of roosts for Noctilio albiventris and to compare the observed patterns in different environments.

Cold and alone? Roost choice and season affect torpor patterns in lesser short-tailed bats.

Seasonal changes in weather and food availability differentially impact energy budgets of small mammals such as bats. While most thermal physiological research has focused on species that experience extreme seasonal temperature variations, knowledge is lacking from less variable temperate to subtropical climates. We quantified ambient temperature (T a) and skin temperature (T sk) responses by individuals from a population of New Zealand lesser short-tailed bats (Mystacina tuberculata) during summer and winter using temperature telemetry. During summer, communal roosts were more thermally stable than T a. During winter, solitary roosts were warmer than T a indicating significant thermal buffering. Communal roost trees were used on 83% of observation days during summer, and individuals occupying them rarely entered torpor. Solitary roosts were occupied on 93% of observation days during winter, and 100% of individuals occupying them used torpor. During summer and winter, bats employed torpor on 11 and 95% of observation days, respectively. Maximum torpor bout duration was 120.8h and winter torpor bout duration correlated negatively with mean T a. Torpor bout duration did not differ between sexes, although female minimum T sk was significantly lower than males. The summer Heterothermy Index varied, and was also significantly affected by T a. Mean arousal time was correlated with sunset time and arousals occurred most frequently on significantly warmer evenings, which are likely associated with an increased probability of foraging success. We provide the first evidence that torpor is used flexibly throughout the year by M. tuberculata, demonstrating that roost choice and season impact torpor patterns. Our results add to the growing knowledge that even small changes in seasonal climate can have large effects on the energy balance of small mammals.

Observations on roost use by the yellow-bellied sheathtail-bat (Saccolaimus flaviventris) in northern New South Wales, Australia

Hollow-bearing trees are recognised as essential habitat features for insectivorous bats and provide sites for mating, the rearing of young, hibernation, protection from predators, and social interaction. The characteristics of hollow-bearing trees used as roosts by insectivorous bats in Australia are poorly known. To help fill this gap, this note presents data on tree roost characteristics for the yellow-bellied sheathtail-bat (Saccolaimus flaviventris) obtained from northern New South Wales, Australia. Of the 19 roost trees observed, most were live Eucalyptus albens trees with an incomplete crown with substantial numbers of dead limbs. Roosts selected were, on average, 9.3 m high with an entrance diameter of 12.7 cm in trees with a mean diameter at breast height of 49.5 cm. All entrance hollows were located at the end of a rotten spout formed when a branch had broken off the tree. These observations are some of the first to document the characteristics of roost trees for this species in New South Wales and this information can be used by land managers to identify and retain suitable roosting habitat for S. flaviventris in the landscape.

Seeing the Forest through the Trees: Considering Roost-Site Selection at Multiple Spatial Scales.

Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis) at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007–2011, we radiotracked 33 Indiana bats (10 males, 23 females) and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum) component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana) or sugar maple of large diameter (>30 cm) of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand structural components that are products of past and current land use interacting with environmental aspects such as landform also are important factors influencing roost-tree selection patterns.

Social network characteristics and predicted pathogen transmission in summer colonies of female big brown bats (Eptesicus fuscus)

Host behavior can affect host-pathogen dynamics, and sociality is predicted to increase risk of pathogen exposure. Many species minimize costs of parasitism by only aggregating seasonally, such as during reproductive periods, but colonial species may still be limited in their potential to evade pathogens. Bats are among the most gregarious mammals and females of many temperate species form maternity colonies in summer where they communally raise pups in both natural and anthropogenic roost structures. Social network structure may differ between natural and anthropogenic roosts in ways that affect pathogen dynamics. We used social network analysis to quantify interactions of big brown bats (Eptesicus fuscus) in a tree-roosting colony, where the colony is divided among multiple trees each day, and a building colony, where most of the colony roosts together each day. We simulated transmission of a pathogen throughout both sets of networks. We tested three hypotheses: (1) network metrics differ between pregnancy and lactation; (2) changing network structure between reproductive stages influences predicted pathogen dynamics; and (3) network metrics and predicted pathogen dynamics differ between colonies of bats in trees versus buildings. Network structure was weaker for bats roosting in trees during pregnancy and lactation compared to bats roosting in a building, and our models showed that a hypothetical pathogen would spread more rapidly for bats in the building colony. Our results are important for understanding variation in social tendencies and pathogen transmission among colonies of bats and have implications for conservation and public health. Host behavior, particularly social behavior, can affect dynamics of wildlife pathogens. Bats are highly social mammals and females of temperate species form colonies in spring and early summer in tree or building roosts. Thermal characteristics of trees and buildings appear to differ in ways that affect roosting behavior and social interactions. We used social network analyses to quantify interactions of big brown bats in tree and building roosts and simulated consequences for pathogen dynamics. Network structure was weaker for bats roosting in trees with more frequent roost switching and relatively diffuse contacts across the network. Our models showed that a hypothetical pathogen could spread up to four times faster in a building colony compared to a colony of bats roosting in trees. Our results are important for understanding how sociality can influence pathogen dynamics in bats and have implications for conservation and public health.

Roost characteristics as indicators for heterothermic behavior of forest‐dwelling bats

AbstractMany forest‐dwelling bats spend their diurnal inactivity period in tree cavities. During this time bats can save energy through heterothermy. A heterothermic response (torpor) is characterized by a lowered body temperature, reduced metabolic rate, and reduction of other physiological processes, and can be influenced by the microclimatic conditions of roost cavities. The thermal and physical characteristics of roosts used by the sympatric, ecologically, and morphologically similar bat species Myotis bechsteinii, M. nattereri, and Plecotus auritus were compared. These three species differ in their heterothermic behavior, with the lowest skin temperatures observed for P. auritus. Therefore, we hypothesized that roosts occupied by the three species should differ in roost characteristics and microclimatic conditions, whereby P. auritus should select colder and thermally less stable roosts. The results showed that horizontal depth of the cavity, diameter of the roost tree, and microclimatic conditions within roosts differed among species. Roosts of P. auritus had the lowest horizontal depth, lowest thermal stability, and lowest mean minimum roost temperatures. Height of the roost, diameter of the roost tree, and vertical depth were also shown to influence microclimatic conditions. With increasing diameter of the tree and increasing horizontal depth, mean minimum roost temperature increased and thermal stability improved. Furthermore, with ascending height above ground insulation and mean roost temperatures increased. Our results imply that species such as P. auritus, which use pronounced torpor as a primary energy saving strategy, prefer colder cavities that support their heterothermic strategy.

Selection of tree roosts by male Indiana bats during the autumn swarm in the Ozark Highlands, USA

ABSTRACTWe identified 162 roosts for 36 male Indiana bats (Myotis sodalis) across 3 study areas in the Ozarks of northern Arkansas, USA, during the autumn swarm (late Aug to late Oct, 2005 and 2006). Bats utilized 14 tree species; snags of shortleaf pine (Pinus echinata) were the most utilized (30% of roosts) and pines were selected over hardwoods. Diameter of trees and snags used for roosting ranged from 7.8 cm to 68.6 cm diameter at breast height (dbh), but bats used trees ≥20 cm dbh at a greater proportion than their availability. Roosts were located in a number of different forested cover classes, including shelterwood and group selection stands that had undergone partial harvesting. Roosts in 2 of 3 study areas showed no differences in proportional use of forest cover classes versus availability of those classes. However, in one study area, mature forests (≥50 yr old) that had been burned once recently and stands burned multiple times over the past 10 years were used at a greater proportion than their availability, whereas mature forests that were not burned were used at a lower proportion than their availability. An examination of stand age data indicated that 98% of all roosts were located in stands ≥38 years old, suggesting that this is an important age threshold for roost selection in the Ozark Mountains. Bats in 2 study areas roosted at lower slopes in the higher elevation portions of the study areas, whereas no selection for topographic aspect were observed in all 3 study areas. Our data indicate that perceived habitat selection by a species may differ within the same geographic region and these differences could be due to factors such as differing selection among individuals, differences in juxtaposition of landscape components and cover types, and differing biological components such as the distribution of predators and predator densities. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Aspen Populus tremula is a key habitat for tree-dwelling bats in boreonemoral and south boreal woodlands in Norway

ABSTRACTThis study aims to identify which tree species bats use as maternity roosts in woodland in southern Norway and, to assess the effectiveness of bat boxes as potential mitigating measures if roosts are lost to forestry or other factors. Radio telemetry was used to find roosts in summer during late pregnancy and through the lactation period by tagging two common species; Daubenton's bats Myotis daubentonii (Kuhl 1817) and soprano pipistrelles Pipistrellus pygmaeus (Leach 1825). In addition, tree roosts were searched using ultrasound detectors at three sites. A total of 35 roosts in natural crevices were found using radio telemetry and through searches with ultrasound detectors and 31 of these roosts were in hollow trees, the majority in aspens Populus tremula L. (n = 30). Some tree roosts were even used by the northern bat Eptesicus nilssonii (Keyserling & Blasius 1839) which is considered a house-dwelling species in Norway. Aspens have some qualities preferred by bats and were both warmer and safer than other hollow tree species in this study area. Bat boxes are used as maternity roosts mainly by soprano pipistrelles at these latitudes, thus at present, there is no suitable alternative to hollow trees that would satisfy all tree-dwelling bat species.

Characteristics of roost cavities used by Lilian's Lovebird Agapornis lilianae in Liwonde National Park, Malawi

Lilian's Lovebird Agapornis lilianae is a non-excavating cavity user of mopane Colophospermum mopane woodlands. We investigated roost characteristics of Lilian's Lovebirds in Liwonde National Park, Malawi. We quantified tree and roost site variables for roost and non-roost trees. Sixty-six roosts were found. Roosts were in large tall mopane trees with a mean diameter at breast height (dbh) of 57.4 ± 1.64 cm, a mean height of 16.5 ± 0.42 m, and with a mean cavity entrance height of 10.0 ± 0.05 m. Non-roost areas had significantly smaller trees (mean dbh = 39.4 ± 1.72 cm). Human disturbance was low in both areas, but browsing of African elephant Loxodonta africana was evident by large areas of stunted mopane woodland recorded in non-roost areas. We recommend that the current Liwonde National Park vegetation map be updated to highlight areas of stunted mopane woodland unsuitable for Lilian's Lovebird roosts. The impact of elephant browsing on large mopane trees should be assessed to understand its impact on the availability of suitable cavities for lovebirds and other tree cavity reliant vertebrate species.

Subtle use of a disturbance mosaic by the south-eastern long-eared bat (Nyctophilus corbeni): an extinction-prone, narrow-space bat

Context Studies of habitat suitability in disturbed landscapes based on species traits can improve predictions about how alternative management strategies are likely to affect threatened species. Aims We studied the south-eastern long-eared bat (Nyctophilus corbeni), which represents a group of bats prone to extinction due to attributes that adapt it to flight within cluttered forest vegetation, typically making them forest-dependent. To support decisions about management of the species in timber production forests, we investigated roost selection and characterised diet in a mosaic of disturbance histories in the Pilliga forests of north-western New South Wales. Methods We caught 54 N. corbeni, radio-tracked 39 individuals and located 41 unique maternity roost trees. Attributes of roost trees were compared with the local neighbourhood and the landscape mosaic of habitat types and logging treatments (recently logged, recently thinned and old regrowth). Preliminary observations were collected on foraging movements. Diet was characterised for maternity and non-maternity seasons using faecal DNA techniques. Key Results Small maternity colonies (&lt;10 bats) were found in hollows and fissures often in exposed locations of trees with a small diameter (means range 23–39 cm) that were usually dead (82.5% of roosts). Buloke Allocasuarina luehmannii was most commonly used for roosting (49%), yet has been overlooked previously as a source of hollows for fauna. Landscape-scale habitat use was subtle: bats avoided roosting in commercially thinned stands and selected old regrowth. Logged and mechanically thinned stands were used in proportion to availability. Nyctophilus corbeni consumed a diverse range of prey in spring (November) and autumn (March), dominated by moths. Conclusions Areas of high stem density, especially those containing dead trees, provide key roosting habitat for N. corbeni and this is likely to be a significant factor explaining the species rarity. Implications Roosting ecology as well as foraging ecology contributes to a species’ sensitivity to disturbance consistent with trait-based predictions. Heterogeneity in the landscape should be maintained when the habitat of N. corbeni is manipulated (e.g. thinned) by retaining a diversity of stem densities, including dense patches (especially with dead A. luehmannii).

Assessment of the occurrence and threats to Hooded Vultures &lt;i&gt;Necrosyrtes monachus&lt;/i&gt; in western Kenyan towns

The Hooded Vulture Necrosyrtes monachus is endemic to Africa and has recently been uplisted to Endangered on the IUCN Red List. Populations of Hooded Vulture in Kenya have declined significantly in recent decades and urban populations exist primarily in western Kenya towns where they typically forage at slaughterhouses and dumpsites. We surveyed seven western Kenyan towns and one neighbouring Ugandan market centre to assess the occurrence and threats to this species using opportunistic observations and interviews with employees at slaughterhouses and dumpsite facilities. We observed 23 Hooded Vultures, 20 in Bungoma Town and 3 in Busia-Uganda. Scavenging vultures were only observed at open-air slaughterhouses or dumpsites. We conducted 34 interviews at 14 facilities of which 23 interviews from six facilities were determined to be of good quality and used for subsequent analyses. At four of the facilities employees confirmed that Hooded Vulture numbers had declined and two respondents indicated declines had occurred from the year 2000 onwards. Possible reasons for declines mentioned by respondents were the introduction of closed-system of slaughterhouses, poisoning of stray dogs, cutting of roost trees, and increased competition for food. There was little evidence of exploitation of the birds for witchcraft or for food.