Colonial Nesting Research Articles

Ecología de la anidación de Crocodylus acutus (Reptilia: Crocodylidae) en Bahía Portete, La Guajira, Colombia

C. acutus is cataloged in critical danger in Colombia. We studied its population at Bahia Portete, in order to survey the nesting activities and to obtain valuable information for a conservation management program. This study was undertaken with the participation of the Wayuü community using the Agreement Conservation Model, and took place during July 2007, August 2008, June and August 2009, and March to August 2010 and 2011. Sampling surveys were made by the use of transects along the coast, in order to find nests. For each nesting area found, we recorded the nests biometrics, eggs and hatchlings, fertility of the eggs and reproductive events. We explored a total of 55.12 km, and determined four nesting areas. Colonial nesting and the environmental variables were factors that affected the hatchling success. From the total of nests found, 37 % were oriented towards North, and 48 % were built next to Stenocereus griseus. Juyi island substrate was mostly constituted by sand (71.9 %, 71.44 %). The average number of eggs by nest was 28.42 ± 6.63, the largest egg diameter was 71.84 ± 3.54 mm, the average nest weight was 81.54 ± 9.99 g, and the hatchlings presented an average length of 25.47 ± 1.16 cm. For this specific site in Colombia, the reproductive period begins in March and ends in August. The few areas of nesting and the 95 % fertility suggest the performance of a conservation management program for this species at Bahía Portete.

Seabird Transfer of Nutrients and Trace Elements from the North Water Polynya to Land during the Mid-Holocene Warm Period, Carey Islands, Northwest Greenland + Supplementary Appendix Figure S1 (See Article Tools)

Seabird guano from large nesting colonies is known to increase trace metal levels in adjacent terrestrial environments today, when global oceans are contaminated with Hg, Cd, and other metals. But the effect of seabird guano in the pre-industrial period has rarely been studied. We used stable C and N isotopic and trace element analyses of a peat core that represents ca. 2000 years of organic matter accumulation to examine the effect on trace elements and nutrients of a seabird colony that existed in northern Baffin Bay during the Holocene Thermal Maximum (ca. 8000–5000 yr BP). Although C and N concentrations were typical of those in other peats, isotopic data identified marine organic matter as the main source of N and a minor source of C in the peat and showed that the unknown seabird was a fish-eating species that was summer-resident for the 2000 yr period. Concentrations of Cd, Br, Sr, and Zn in peat were up to an order of magnitude higher than in ombrotrophic (air-fed) bogs elsewhere, whereas Hg and Cu concentrations were similar to those in other peats, suggesting relatively low levels of Hg and Cu in the guano. This surprising result for Hg contrasts with studies on modern seabirds, in which guano markedly increased environmental Hg concentrations. It could be a consequence of Hg concentrations in Arctic marine food webs in the pre-industrial period that were an order of magnitude lower than those of today.

Life Inside an Acorn: How Microclimate and Microbes Influence Nest Organization in Temnothorax Ants

AbstractNests provide a buffer against environmental variation, but conditions may also vary at different locations within a nest. Conditions can vary based on abiotic factors, such as moisture and temperature, as well as biotic factors, such as the presence of microbes and potential pathogens. Therefore, characterizing how animals adjust their position inside their nests to track microclimate preferences while at the same time preventing pathogen exposure is necessary to understand the benefits nests provide. Here we studied how colonies of the acorn‐nesting ant Temnothorax curvispinosus responded to experimental manipulation of moisture, temperature, and microbial growth inside their nests. Colonies showed no response to differences in moisture and moved to the bottom of the acorn regardless of moisture treatment. When nests were heated from the top to simulate warming by the sun, workers preferentially moved brood to the warm, upper half of the acorn, which would stimulate brood development. Finally, the strongest factor that influenced colony position was the presence of microbes inside the nest—colonies avoided the bottom of the nest when it was inoculated with microbes, and colonies in new acorns shifted to the top of the acorn over time as mold and other microbes had time to grow. The relatively strong response of T. curvispinosus to microbial growth inside their nests suggests that pathogen pressures—in addition to microclimate—have a significant impact on how colonies use nest spaces. Social insects are known to invest heavily in antimicrobial compounds that kill or slow the growth of microbes, but avoidance may represent an additional line of defense to prevent pathogen exposure.

Sterols and Stanols Preserved in Pond Sediments Track Seabird Biovectors in a High Arctic Environment.

Seabirds are major vertebrates in the coastal ecosystems of the Canadian High Arctic, where they transport substantial amounts of marine-derived nutrients and pollutants from oceans to land by depositing guano and stomach oils to their nesting area, which often includes nearby freshwater ponds. Here we present novel indicators for evaluating the impact of seabirds on freshwater ecosystems. The ratio of cholesterol/(cholesterol + sitosterol) in pond sediments showed significant enrichment near a nesting colony of northern fulmars (Fulmarus glacialis) and was significantly correlated with ornithogenic enrichment of sediment as determined by sedimentary δ(15)N. The sterol ratio was also correlated with several bioaccumulative persistent organic pollutants (POPs), suggesting its usefulness in tracking biovector enrichment of contaminants. Human-derived epicoprostanol was also analyzed in the sediments, and its relationship with an abandoned, prehistoric camp was recorded, suggesting its potential as a tracer of prehistoric human activities in the Arctic. Sterols and stanols preserved in sediments appear to be useful geochemical tools that will inform our understanding of migratory species and the presence of prehistoric human populations in the Arctic, and possibly other animal populations.

Nesting Behaviour of the Giant Honeybees Apis dorsata Occurring in Jhargram, West Bengal, India

The giant honeybees Apis dorsata are habituated to construct combs in trees, houses, caves as well as in overhead water reservoir occurring in their nesting localities. To verify their preference for nesting sites if any, surveys were conducted in recent years (2013–16), during nesting seasons of these bees in Jhargram area of West Bengal, India. It is revealed that A. dorsata construct their combs in big, tall, aged simul (Bombax ceiba), bot (Ficus benghalensis) trees mostly, irrespective of localities. Also they were seen to construct nest at the underside of the overhead water reservoir ignoring nesting potential trees occurring nearby. Of course, nesting in the houses, and on the walls of culvert is not uncommon. As the bees constructed more than 100–200 nests at the same nesting site e.g., a tree or/and an overhead water reservoir, depending upon the availability of space for construction of nest it is concluded that these insects prefer colonial nesting.

Interspecific interactions in nesting and feeding urban sites among introduced Monk Parakeet (Myiopsitta monachus) and syntopic bird species

Monk Parakeet (Myiopsitta monachus) is a successful invader of many European urbanised habitats. Here, we report evidence of interspecific interactions between this species and some synanthropic co-occurring birds in three urban parks of Rome (central Italy). In both nesting and feeding sites, we recorded 158 interactions with seven syntopic species in eight colonial focal nests (0.74 events/hr). The number and frequency of interactions significantly differ among nests and species, the Italian Sparrow (Passer italiae) being the most interactive species. For this species, the frequency of interactions was normally distributed between different months with a peak in June. We also observed a case of nest cohabitation, as well as predatory attacks carried out by Hooded Crow (Corvus cornix). As far as foraging sites are concerned, 11 out of 74 clusters of parakeets (15%) hosted four bird species, mainly Starling, Sturnus vulgaris, but we did not observe any interactions. Although Monk Parakeet is a social bird generally tolerant towards other species near their nests and in foraging areas, we observed interspecific interactions in nesting sites as a response to competitive or predatory mechanisms. Italian Sparrows interact because they use parakeet nests as a secondary structure for nesting (cohabitation) and, probably, because of the wide availability of food resources (invertebrates) useful for juvenile recruitment. The interaction of parakeets with Hooded Crow is a response to predatory attacks on eggs or juveniles. However, interspecific interactions seem to be occasional events in nesting sites and are apparently absent in feeding sites, where competitive behaviour is probably reduced due to high availability of plant resources. In urbanised areas, where Monk Parakeets have recently been introduced, the number of competitors and predators might be very reduced (both in number of events and species) in comparison to native areas where competition and predatory mechanisms reflect long-term co-evolutionary dynamics.

Honey Bee Inhibitory Signaling Is Tuned to Threat Severity and Can Act as a Colony Alarm Signal.

Alarm communication is a key adaptation that helps social groups resist predation and rally defenses. In Asia, the world’s largest hornet, Vespa mandarinia, and the smaller hornet, Vespa velutina, prey upon foragers and nests of the Asian honey bee, Apis cerana. We attacked foragers and colony nest entrances with these predators and provide the first evidence, in social insects, of an alarm signal that encodes graded danger and attack context. We show that, like Apis mellifera, A. cerana possesses a vibrational “stop signal,” which can be triggered by predator attacks upon foragers and inhibits waggle dancing. Large hornet attacks were more dangerous and resulted in higher bee mortality. Per attack at the colony level, large hornets elicited more stop signals than small hornets. Unexpectedly, stop signals elicited by large hornets (SS large hornet) had a significantly higher vibrational fundamental frequency than those elicited by small hornets (SS small hornet) and were more effective at inhibiting waggle dancing. Stop signals resulting from attacks upon the nest entrance (SS nest) were produced by foragers and guards and were significantly longer in pulse duration than stop signals elicited by attacks upon foragers (SS forager). Unlike SS forager, SS nest were targeted at dancing and non-dancing foragers and had the common effect, tuned to hornet threat level, of inhibiting bee departures from the safe interior of the nest. Meanwhile, nest defenders were triggered by the bee alarm pheromone and live hornet presence to heat-ball the hornet. In A. cerana, sophisticated recruitment communication that encodes food location, the waggle dance, is therefore matched with an inhibitory/alarm signal that encodes information about the context of danger and its threat level.

Environmental enrichment rescues the effects of early life inflammation on markers of synaptic transmission and plasticity

Environmental enrichment (EE) has been successful at rescuing the brain from a variety of early-life psychogenic stressors. However, its ability to reverse the behavioral and neural alterations induced by a prenatal maternal infection model of schizophrenia is less clear. Moreover, the specific interactions between the components (i.e. social enhancement, novelty, physical activity) of EE that lead to its success as a supportive intervention have not been adequately identified. In the current study, standard housed female Sprague-Dawley rats were administered either the inflammatory endotoxin lipopolysaccharide (LPS; 100μg/kg) or pyrogen-free saline (equivolume) on gestational day 15. On postnatal day 50, offspring were randomized into one of three conditions: EE (group housed in a large multi-level cage with novel toys, tubes and ramps), Colony Nesting (CN; socially-housed in a larger style cage), or Standard Care (SC; pair-housed in standard cages). Six weeks later we scored social engagement and performance in the object-in-place task. Afterwards hippocampus and prefrontal cortex (n=7–9) were collected and evaluated for excitatory amino acid transporter (EAAT) 1-3, brain-derived neurotrophic factor (BDNF), and neurotrophic tyrosine kinase, receptor type 2 (TrkB) gene expression (normalized to GAPDH) using qPCR methods. Overall, we show that gestational inflammation downregulates genes critical to synaptic transmission and plasticity, which may underlie the pathogenesis of neurodevelopmental disorders such as schizophrenia and autism. Additionally, we observed disruptions in both social engagement and spatial discrimination. Importantly, behavioral and neurophysiological effects were rescued in an experience dependent manner. Given the evidence that schizophrenia and autism may be associated with infection during pregnancy, these data have compelling implications for the prevention and reversibility of the consequences that follow immune activation in early in life.

Population trends over 50 years of a Pied Imperial-Pigeon breeding colony on North Brook Island, a tropical Great Barrier Reef island, Australia

The Pied Imperial-Pigeon (Ducula bicolor) is a summer migrant to northern Australia, and nests colonially on many islands of the Great Barrier Reef, Queensland. Numbers are perceived to have declined as a result of large-scale shooting in the past and clearing of their mainland feeding grounds. To obtain evidence of any population changes, 1–10 counts were made each breeding season of the evening flight from the mainland to a nesting colony on North Brook Island. The counts began in 1965 and have continued for 50 years. The count represents one individual of a pair that visits the mainland to feed and returns in the evening. In the 1965–66 breeding season, the December count (the count used to compare years) was 4692 birds. Over the following three seasons, numbers declined to a low of 1451 birds in 1968–69; this decline was attributed to shooting of up to 1100 birds at a time. Large-scale shooting stopped in 1968 and was followed by a steady exponential increase (y = 3370.4e0.0908x in numbers over 23 years to 29 818 birds in the 1992–93 season. Numbers have fluctuated between ∼25 000 and 35 000 individuals over the following 18 years. A tropical cyclone of extreme intensity affected the pigeons’ breeding site on North Brook Island and their mainland feeding areas in February 2011. In the following breeding season of 2011–12, numbers fell to 5311, but recovered to 21 088 in the 2012–13 season. The dramatic drop in numbers was attributed to the pigeons moving elsewhere for the 2011–12 season. It is predicted that the post-cyclonic number of 21 088 will take 4 years to recover to 30 000. The counts are a simple and somewhat coarse measure of population trends, but provide a population baseline for more sophisticated studies on the movements of pigeons and their responses to long-term changes in habitat and climate.

Warfare in stingless bees

Bees are well known for being industrious pollinators. Some species, however, have taken to invading the nests of other colonies to steal food, nest material or the nest site itself. Despite the potential mortality costs due to fighting with an aggressive opponent, the prospects of a large bounty can be worth the risk. In this review, we aim to bring together current knowledge on intercolony fighting with a view to better understand the evolution of warfare in bees and identify avenues for future research. A review of literature reveals that at least 60 species of stingless bees are involved in heterospecific conflicts, either as attacking or victim colonies. The threat of invasion has led to the evolution of architectural, behavioural and morphological adaptations, such as narrow entrance tunnels, mud balls to block the entrance, decoy nests that direct invaders away from the brood chamber, fighting swarms, and soldiers that are skilled at immobilising attackers. Little is known about how victim colonies are selected, but a phylogenetically controlled analysis suggests that the notorious robber bee Lestrimelitta preferentially attacks colonies of species with more concentrated honey. Warfare among bees poses many interesting questions, including why species differ so greatly in their response to attacks and how these alternative strategies of obtaining food or new nest sites have evolved.

The complexity of ecological impacts induced by great cormorants

Following decades of global extermination, the general population of the great cormorant (Phalacrocorax carbo L.) is on the rise. The lack of regular predators, highly skilled fish rapacity, rapid metabolism, significant rate of excretion and ability to form large nesting colonies on relatively small areas lead to numerous environmental consequences of cormorant presence. Here we comprehensively review the occurrence and distribution of this species and, in particular, its multi-faceted impact on terrestrial and aquatic ecosystems and the main routes through which these impacts are being manifested. The bird-induced chemical loading and its biological and ecological consequences, and the effects on microbial pollution and pathogen dispersion are discussed in particular. The need for further investigation to fully elucidate particular effects is stressed throughout the paper. It is concluded that the environmental effects of great cormorants are rather complex, can lead to serious ecosystem modifications and that the presence of these birds should be taken into consideration in ecological assessment and monitoring.

Application of video recording technology to improve husbandry and reproduction in the carmine bee-eater (Merops n. nubicus).

Incorporating technology with research is becoming increasingly important to enhance animal welfare in zoological settings. Video technology is used in the management of avian populations to facilitate efficient information collection on aspects of avian reproduction that are impractical or impossible to obtain through direct observation. Disney's Animal Kingdom(®) maintains a successful breeding colony of Northern carmine bee-eaters. This African species is a cavity nester, making their nesting behavior difficult to study and manage in an ex situ setting. After initial research focused on developing a suitable nesting environment, our goal was to continue developing methods to improve reproductive success and increase likelihood of chicks fledging. We installed infrared bullet cameras in five nest boxes and connected them to a digital video recording system, with data recorded continuously through the breeding season. We then scored and summarized nesting behaviors. Using remote video methods of observation provided much insight into the behavior of the birds in the colony's nest boxes. We observed aggression between birds during the egg-laying period, and therefore immediately removed all of the eggs for artificial incubation which completely eliminated egg breakage. We also used observations of adult feeding behavior to refine chick hand-rearing diet and practices. Although many video recording configurations have been summarized and evaluated in various reviews, we found success with the digital video recorder and infrared cameras described here. Applying emerging technologies to cavity nesting avian species is a necessary addition to improving management in and sustainability of zoo avian populations.

Avian Malaria is Absent in Juvenile Colonial Herons (Ardeidae) but notCulex pipiensMosquitoes in the Camargue, Southern France

Apicomplexan blood parasites Plasmodium and Haemoproteus (together termed “Avian malaria”) and Leucocytozoon are widespread, diverse vector-transmitted blood parasites of birds, and conditions associated with colonial nesting in herons (Ardeidae) and other waterbirds appear perfect for their transmission. Despite studies in other locations reporting high prevalence of parasites in juvenile herons, juvenile Little Egrets (Egretta garzetta) previously tested in the Camargue, Southern France, had a total absence of malaria parasites. This study tested the hypotheses that this absence was due to insufficient sensitivity of the tests of infection; an absence of infective vectors; or testing birds too early in their lives. Blood was sampled from juveniles of four species shortly before fledging: Little Egret (n = 40), Cattle Egret (Bubulcus ibis; n = 40), Black-crowned Night-Heron (Nycticorax nycticorax, n = 40), and Squacco Heron (Ardeola ralloides; n = 40). Sensitive nested-Polymerase Chain Reaction was used to test for the presence of parasites in both birds and host-seeking female mosquitoes captured around the colonies. No malaria infection was found of in any of the heron species. Four different lineages of Plasmodium were detected in pooled samples of female Culex pipiens mosquitoes, including two in potentially infective mosquitoes. These results confirm that the absence of malaria parasites previously demonstrated in Little Egret is not due to methodological limitations. Although the prevalence of infection in mosquitoes was low, conditions within the colonies were suitable for transmission of Plasmodium. These colonial heron species may have evolved strategies for resisting malaria infection through physiological or behavioral mechanisms.

The Role of Non-Foraging Nests in Polydomous Wood Ant Colonies.

A colony of red wood ants can inhabit more than one spatially separated nest, in a strategy called polydomy. Some nests within these polydomous colonies have no foraging trails to aphid colonies in the canopy. In this study we identify and investigate the possible roles of non-foraging nests in polydomous colonies of the wood ant Formica lugubris. To investigate the role of non-foraging nests we: (i) monitored colonies for three years; (ii) observed the resources being transported between non-foraging nests and the rest of the colony; (iii) measured the amount of extra-nest activity around non-foraging and foraging nests. We used these datasets to investigate the extent to which non-foraging nests within polydomous colonies are acting as: part of the colony expansion process; hunting and scavenging specialists; brood-development specialists; seasonal foragers; or a selfish strategy exploiting the foraging effort of the rest of the colony. We found that, rather than having a specialised role, non-foraging nests are part of the process of colony expansion. Polydomous colonies expand by founding new nests in the area surrounding the existing nests. Nests founded near food begin foraging and become part of the colony; other nests are not founded near food sources and do not initially forage. Some of these non-foraging nests eventually begin foraging; others do not and are abandoned. This is a method of colony growth not available to colonies inhabiting a single nest, and may be an important advantage of the polydomous nesting strategy, allowing the colony to expand into profitable areas.

COLONIAL DEFENSE BEHAVIOR IN DOUBLE-CRESTED AND PELAGIC CORMORANTS

COLONIAL DEFENSE BER A VIOR IN DOUBLE-CRESTED AND PELAGIC CORMORANTS DOUGLAS SIEGEL-CAUSEY 1 AND GEORGE L. H UNT, JR. Department of Ecology and Evolutionary Biology, University of California, Irvine, California 92717 USA ABsTRACT.- We eicamine the predictions, based upon the hypotheses of Coulson (1968), Ham- ilton (1971), and Vine (1971), that (I) spedes whose colonies are accessible to predators should form tighter groupings and have fewer isolated nests than those with reduced accessibility to predators, (2) nests at the center should be less subject to predation than those at the edge of a colony, (3) nests both in the center and with reduced accessibility should have the lowest predation pressure of all nests, and (4) individuals that nest in accessible locations should have more vigorous and more sustained antipredator behaviors than those individuals unlikely to come frequently in contact with predators. To test these predictions, we compare intrusions by two predators, the Northwestern Crow (Corvus cauri11us) and the Glaucous-winged Gull (Larus glaucescens), at isolated and grouped nests of the cliff-face nesting Pelagic Cormorant (Phalacrocorax pelagicus) and cliff-top nesting Double-crested Cormorant (P. auritus) on Mandarte Island, British Colum- bia. Both crows and gulls preferred to visit the edge nests of both species, especially those on level ground. The steeper and more central the nest location, the less likely was visitation. Gulls were restricted by topography from entering the Pelagic colony, while crows were able to land in either colony. Predator success was high only in flat, accessible areas. Both cormorant species depend upon the habitat to deter predator access: the Double-crested Cormorant utilizes a defense regime of energetic and aggressive behaviors; the Pelagic Cormorant uses a much less effective defense and depends much more on the habitat as a necessary part of nest defense. Received 11 July 1980, accepted 21Ja11uary1981. WE here examine aspects of colonial nesting in relation to their effectiveness as protection against intruding predators. Nesting phenology (Nelson 1966, 1970), lo- cation within the colony (Coulson 1968), and the topography of the colony (Nelson 1967, Nettleship 1972) have been identified as actual or potential factors in deter- mining the likelihood that a particular nest will be subject to predation. H amilton (1971) hypothesized that the clumping of prey provides a significant defense against predation, and Coulson (1968) and Vine (1971) hypothesized that individuals at the center of a group will be at a lesser riisk than those at the edge. To test the hypotheses concerning the importance of nest location in predator avoidance, we examine the interactions between two species of prey, the Double- crested Cormorant (DCC: Phalacrocorax auritus) and the Pelagic Cormorant (PC: P. pelagicus), and two species of predators, the Northwestern Crow (Con.ms caur- inus) and the Glaucous-winged Gull (Larus glaucescens), at cormorant nesting col- onies on Mandarte Island, British Columbia, Canada. In this study, we had the opportu nity to compare the activity and effect of a highly maneuverable predator (the Northwestern Crow) and a relatively clumsy predator (the Glaucous-winged Gull) as they attempted to steal eggs and small chicks from cormorant nests. Because the two species of cormorant prefer different nesting habitats and consequently have different structures for their colonies, we were able to compare the antipredator behaviors and their effectiveness for cormorants nesting on cliffs (Pelagic Cormorant) and for those nesting on level areas (Double-crested Cormorant) and for tightly clumped as well as loosely grouped nests. ' Present address: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721 USA. The Auk 98: 522-531. July 1981

Накопление тяжелых металлов стеблями, цветками, нектаром и пыльцой ивы козьей, произрастающей на селитебных территориях

От возможности использования пчелами ранневесенних медоносных растений зависит развитие пчелиных семей и их потенциальная продуктивность. Однако пыльца и нектар ив, произрастающих на селитебных территориях вблизи автомобильных дорог, может подвергаться загрязнению тяжелыми металлами. Исследование проведено в период массового цветения ив, происходившего во второй декаде апреля. У цветущих растений отбирали 1 – 2-летние побеги. Для отбора пыльцы и нектара использовали семьи пчел, находившиеся на расстоянии 300 – 400 м от ив, цветки которых активно посещались пчелами. Пыльцу отбирали навесными пыльцеуловителями, а нектар, доставляемый пчелами в гнездо, — из ячеек сот. Чтобы исключить в пробах нектара ранее собранного углеводного корма, в период цветения ив в гнезда пчелиных семей помещали пустые соты. Их отбирали в течение дня, чем исключалась переработка нектара в мед. Содержание тяжелых металлов в минерализатах определяли методом атомно-адсорбционной спектрометрии. Содержание анализируемых элементов в стеблях, цветках, пыльце и нектаре ив варьировало в широких пределах. Высоким содержанием железа отличались стебли, цветки и нектар, а цинка — стебли, пыльца и нектар. Содержание свинца в нектаре ивы превосходило предельно допустимую норму в 12,1 раза. При переработке пчелами нектара в мед содержание в нем свинца существенно уменьшается. Установлено, что в таких условиях слабо или совсем не прослеживается фильтрующая функция барьеров на границах разных органов растения. Загрязнение тяжелыми металлами нектара и пыльцы, добываемых пчелами на техногенно загрязненных территориях, может выступать в качестве одной из причин увеличения их гибели, наблюдаемой в последние годы.

Sabine's Gull (Xema sabini) Nesting Aggregations in Western Alaska

Abstract We analyzed data on the size of nesting aggregations of Sabine's Gulls (Xema sabini) observed in the Yukon–Kuskokwim Delta (YKD), Alaska, between 1986 and 2013, to determine whether the species is a “solitary low-density nester” there, as in other parts of its range. Data for 1087 nests show that 56% of Sabine's Gull nests were solitary and that <3% of aggregations exceeded 10 nests, although factors positively correlated with the evolution of colonial nesting, including exposure of nests to predators, aquatic habitat, and absence of feeding territories, apply to Sabine's Gulls nesting in the YKD. Although Sabine's Gulls in the YKD were most often solitary nesters, in 2010 we found a 102-nest aggregation on a small island in the study area, larger than any reported for the species. Among all aggregated nests, 75.4% occurred on islands, and only 13.9% along shorelines, while 39.8% of all solitary nests occurred on islands, and 39.3% along shorelines. The proportion of Sabine's Gull nests in the YK...

AQUEOUS TRANSPORT OF GULL NESTS AND EGGS: TAPHONOMIC IMPLICATIONS FOR FOSSIL AMNIOTE NESTS

Abstract We report the flooding and transport of glaucous-winged gull (Larus glaucescens) nests and eggs in response to high tides at a nesting colony in Washington State. Affected nests were located on the beach bordering a small marina. Flooding and transport most commonly occurred during very high tides. Nests with eggs, nests without eggs, and eggs without nests were observed floating offshore. Our observations have implications for the interpretation of fossilized amniote nests and eggs, namely that a given fossil nest cannot be assumed a priori to have been preserved in situ without careful consideration of nest structure and lithological features of the preservation site. Also, prior to preservation, a fossil egg or egg clutch may have been transported by a floating nest functioning as a transport vessel, even if at the time of discovery evidence for the nest has disappeared.

Nesting colonies of little cormorant (Phalacrocorax niger) in different study areas of Bangladesh

A study was done on nesting colonies of Little Cormorant (Phalacrocorax niger) in different study areas of Bangladesh from 2003 to 2005. The study sites were Eidgah in Cox’s Bazar, Bhuyapur in Tangail, Bhairab and Tarail Upazilla in Kishorganj, Dimla in Nilfamari, Singair Upazilla in Manikganj and Matlab in Chandpur district. These sites were visited at regular interval to know about the characteristics of different nesting colonies and causes of their decline and threats for the Little Cormorant. The village markets and school areas were visited to know about the location of nests, different threats against them and information about the present situation of Little Cormorant and also for creation of awareness for their conservation. The nesting habitats of the Little Cormorant were situated in the homestead areas in all the cases. The highly preferred sites for nesting were near a pond (75%). Bamboo (Bambusa arundinacea) was the highly preferred nesting trees (25%). The nesting height varied from 8.84 m to 10.66 m. Association of the Little Cormorant in the colony was found with Ardeaola grayii (30%), Egretta garzetta (30%), Mesophoyx intermedia (30%), Casmerodius albus (5%) and Pteropus giganteus (5%). The nesting colonies of the Little Cormorant were destroyed by human (92.9%) and river erosion (7.1%). It was observed that awareness campaign will help for the conservation of the bird.Bangladesh J. Zool. 42(1): 35-44, 2014

Butterflies that trick ants with sound

Larvae of parasitic Maculinea butterflies use acoustic mimicry to induce host ants to adopt and care for them.