Feeding Flocks Research Articles

Seed dispersal between aquatic and agricultural habitats by greylag geese

Waterbirds disperse plant seeds within and between aquatic and terrestrial ecosystems in their faeces. However, seed dispersal distances, connectivity among habitat types, and implications for dispersal of weeds remain unquantified in agricultural landscapes. Therefore, we GPS-tagged 31 greylag geese Anser anser and collected 300 faecal samples from feeding flocks in seven agricultural habitats (four cereals, hayfields, pasture, and strawberries) across two landscapes in southern Sweden. We identified intact seeds, determined key plant traits, and tested three hypotheses: (1) geese ingest, transport, and egest seeds from a wide range of terrestrial and aquatic plants, including weeds and alien species; (2) the community and trait composition of plant seeds in faeces vary between habitat types; and (3) seed dispersal by geese is a directional dispersal mechanism that connects some habitat types more than others. We recovered 131 seeds from 41 plant species (19 families), including nine agricultural weeds and one alien species. Many seeds were from aquatic plants (45%), dispersed into terrestrial habitats. A connectivity network formed between habitat types (as nodes) and direct flights (as links) revealed that all agricultural habitats were directly connected with each other, although 66% of flights were between aquatic and agricultural habitats. Geese spent most time at lakes (34%), pastures (14%), barley (10%) and wheat (8%) fields, which were also the most interconnected habitats, with high seed species richness and seed abundance in faecal samples. Combining waterfowl movement data with faecal analysis provided support for all three hypotheses. Geese may contribute to previously overlooked agricultural conflicts through weed dispersal. Proximity to aquatic habitats suitable for roosting may increases the use of agricultural habitats, and potentially the seed dispersal into them.

Variation in foraging strategies of New Zealand albatross species within a dominance hierarchy

ABSTRACT Co-occurring species sharing a limited resource are thought to adopt alternative strategies to coexist. Here, we investigate four species of co-occurring albatrosses in southern New Zealand that share food resources but differ in dominance status to test for variation in strategies to acquire supplemental food provided by ecotourism boats. We found evidence for distinct foraging strategies consistent with each species’ dominance rank. Buller’s albatross (Thalassarche bulleri) was the most subordinate species and frequently pursued scraps of fish on the periphery of the feeding flocks and avoided interacting with other species. Salvin’s albatross (Thalassarche salvini) and White-capped albatross (Thalassarche cauta) were intermediate in dominance status; both had fast responses to fish and typically pursued the largest fish scraps, though T. cauta successfully stole fish while T. salvini did not. In contrast, Southern Royal albatross (Diomedea epomophora) was the dominant species and did not avoid interactions with other species and pursued the largest fish scraps but was slower to respond compared with some subordinates. Natural food sources approximate the scenarios seen behind ecotourism boats, suggesting that differences in foraging strategies are likely present without human intervention. Overall, our results suggest that foraging strategies associated with dominance hierarchies could help structure seabird communities.

PHYLOGENETIC RELATIONSHIPS OF GUIMARAESIELLA AND PRICEIELLA (PHTHIRAPTERA: ISCHNOCERA) FROM BABBLERS AND NON-BABBLERS (PASSERIFORMES).

Babblers (Passeriformes: Leiothrichidae, Pellorneidae, Timaliidae) are parasitized by more genera of lice of the Brueelia complex than any other group of songbirds. However, the relationships of these louse groups are poorly known. We here try to resolve the relationships between Guimaraesiella (Guimaraesiella), Guimaraesiella (Cicchinella), and their putative sister group Priceiella by using mitochondrial cytochrome c subunit 1 (COI), 12S, and 16S sequences. Our data indicate that G. (Cicchinella) forms a monophyletic group of lice from babblers, but the relationship between G. (Guimaraesiella), G. (Cicchinella), and Priceiella could not be resolved. Moreover, the position of the third lineage of babbler-specific lice, containing only the aberrant species Guimaraesiella montisodalis, is unresolved. Morphologically, this species is different from all other Guimaraesiella in several characters and may represent a distinct lineage. We present some data indicating that (1) the Nanling Mountain range may be a biogeographical barrier to chewing lice and (2) host participation in mixed-species feeding flocks may influence host associations in Brueelia-complex chewing lice.

Effects of feed efficiency and diet on performance and carcass characteristics in growing wether lambs

Selection for feed efficiency may lead to decreased production inputs; however, associations between feed efficiency and other phenotypic traits of interest in sheep are not well understood. The objectives of this study were to 1) determine the effect of diet on feed intake traits, 2) determine the effect of dietary change on residual feed intake (RFI) and performance traits, and 3) determine relationships of RFI with carcass characteristics in lambs fed either a concentrate or forage-based diet. In Trial 1, growing wethers (initial live weight (LW) = 51.3 ± 1.2 kg; n = 78) of Hampshire (n = 35), Rambouillet (n = 26), and Suffolk (n = 17) breed types were blocked by breed and initial LW and randomly allocated to receive a concentrate (50.2% corn, 31.0% wheat middlings, 10.0% corn gluten, 2.5% cane molasses, 1.8% calcium carbonate, 1.0% dried distillers grains with soluble, 0.8% calcium sulfate, 0.2% potassium chloride, 0.4% trace minerals and vitamins; 91.6% DM; 12.1% CP, 17.6% NDF, 3.0 Mcal/kg ME; n = 40) or forage-based (67.7% alfalfa, 27.5% wheat middlings, 2.5% cane molasses, 1.3% salt, 0.6% calcium carbonate, 0.3% trace minerals and vitamins; 92.3% DM, 16.2% CP, 36.3% NDF, 2.3 Mcal/kg ME; n = 38) pelleted diet. Individual feed intake was recorded using a GrowSafe System for 49 days and RFI was estimated for each wether. Using RFI to rank the wethers for feed efficiency, the 20% most (n = 8) and the 20% least (n = 8) efficient wethers from each diet (n = 32 total) were slaughtered and carcass data were recorded. Remaining wethers from the forage diet were subsequently changed to the concentrate diet for Trial 2; individual feed intake was again collected using the GrowSafe System for 79 days, and RFI calculated for each wether. The MIXED procedure of SAS was used to determine the effect of diet and diet change on performance traits in Trials 1 and 2, respectively, and the effects of diet, RFI class (most or least efficient), and their interaction on carcass traits using data from selected wethers (n = 32) from Trial 1; breed and pen were included as random effects. The CORR procedure of SAS was used to determine relationships of RFI with performance traits and carcass characteristics. Overall, feed intake was less variable for concentrate-fed (σ2 = 0.13 kg2) than forage-fed wethers (σ2 = 0.25 kg2). Feed intake and average daily gain (ADG) were greater (P ≤ 0.001) in forage-fed compared to concentrate-fed wethers, although the gain to feed ratio (G:F) was not affected by diet type (P = 0.23). While RFI and RFI rankings were moderately correlated (r = 0.51, r = 54, respectively; P ≤ 0.02) in wethers subjected to the diet change (forage to concentrate), some re-ranking was observed, especially in low efficiency lambs. Boneless cut percentage tended (P = 0.10) to be greater in forage versus concentrate wethers; there were no other effects (P ≥ 0.13) of diet on carcass measures. Residual feed intake and USDA quality grade tended (P = 0.10) to be positively correlated, but no other relationships (P ≥ 0.17) between RFI and carcass measures were observed. These data suggest that feed intake and ADG are affected by diet type, and that greater variation in feed intake is associated with a forage-based pelleted diet. Additionally, selection against low feed efficiency may be most effective in improving flock feed efficiency genetics when compared with selection for greater efficiency. Furthermore, selection for RFI should not unfavorably affect carcass traits in sheep.

Which birds participate in mass concentrations of Bramblings Fringilla montifringilla?\u2014Ring recoveries, biometry, age and sex composition

The Brambling Fringilla montifringilla combines several special features of migration and wintering: differential migration according to age and sex groups, large differences in winter densities as a response to food availability, and flocking behaviour as a response to local mass fructification of the beech Fagus sp. resulting in roosts of several million birds. This study examines (a) whether Bramblings participating in mass concentrations originate from different, or additional, breeding grounds compared with birds present in normal winters, and (b) how differential migration according to age and sex groups combines with irruptive migration and with congregations in mass roosts, i.e., whether the benefits from mass concentrations differ between age and sex groups. Wing biometry (wing length, lengths of outer primaries, and wing pointedness) did not vary geographically, as shown by museum skins, and was therefore not helpful to reveal differences in origin between birds of mass concentrations and normal winters. The extent of the post-juvenile moult was smaller in mass concentration birds and suggests that slightly later-born juveniles, i.e., born further east or north, participate in mass concentrations. Ringing recoveries could not demonstrate a difference in breeding range origin of Bramblings which participate in mass concentrations versus Bramblings in normal winters in Switzerland. However, this may be due to insufficient recoveries of ringed birds. A rough estimate suggests that the number of Bramblings migrating SW on a broad front across Europe could be sufficient to form mass concentrations of up to 10 million birds which are halted by a large area of beech mast. Across Europe, the proportion of juvenile males decreased towards south (i.e., with increasing migration distance) in autumn migrants and wintering birds, while adult females showed the opposite pattern, and adult males and juvenile females were intermediate. Mass concentrations in Switzerland were composed of significantly more adults, especially adult males, and fewer juveniles, particularly juvenile females, while the sex–age composition outside mass concentrations was similar to normal winters. Adults and females likely benefit from wintering further south where snow is less likely to cover food of this ground-feeding finch. On the other hand, the costs of migration are probably substantial in terms of direct costs or indirectly in terms of reaching the breeding grounds, so that juvenile males prefer to winter closer to the breeding area than adults. Feeding in large flocks in beech mast areas incurs the high risk of being cut off from this food by snowfall. Adult males are apparently best adapted to this risk, and hence predominate in mass concentrations.

Egg enrichment with vitamin D: The Sunshine Eggs projects

AbstractVitamin D deficiency is a significant public health issue in the UK with almost one in five adults having poor vitamin D status and most people failing to meet the Reference Nutrient Intake of 10 µg/day. There is an urgent need to address poor population vitamin D status through the development of food‐based strategies. Eggs can be enriched with vitamin D through manipulating vitamin D content in hens’ feed. The Sunshine Eggs project was launched in 2015 through Innovate UK funding and brought together Noble Foods Ltd, DSM Nutritional Products Ltd and Newcastle University. The research demonstrated that feeding flocks of commercial hens up to 75 µg of 25‐D/kg (25‐hydroxyvitamin D3 via Rovimix® Hy‐D®) of feed for 6 weeks improved egg total vitamin D content by 40%. These results informed the reformulation of the UK’s leading free‐range egg brand ‘Happy Egg’ in October 2018, offering vitamin D–enriched eggs to the consumer. This article outlines the aims of a second Innovate UK‐funded Sunshine Eggs 2 project, which seeks to maximise the commercial potential of vitamin D–enriched eggs through several objectives. These relate to understanding (1) how storage/cooking methods affect egg vitamin D content; (2) whether enriched egg consumption improves vitamin D status in a human intervention trial; (3) consumer attitudes towards enriched eggs; and (4) market research to identify commercial opportunities for enriched eggs. The project seeks to drive fundamental impact across academic, commercial and public health nutrition sectors, in helping to offer viable vitamin D–enriched foods for UK consumers.

Harvesting of Onion Grass, Romulea rosea L. by Sulphur‐crested Cockatoo, Cacatua galerita Latham

SummaryThe harvesting of Onion Grass (Romulea rosea) corms by flocks of Sulphur‐crested Cockatoo (Cacatua galerita) is well known. Individual birds and large flocks feed on the weed in pastures, grasslands and recreational turf. Flocks of Sulphur‐crested Cockatoo were observed feeding on Onion Grass at seven sites along the Maribyrnong River at Keilor, Victoria. Flock size and feeding habits were noted, as were the depth of corms, the time taken to remove corms from the ground and the number of eaten and lifted but uneaten corms. From the data collected, it was estimated that an individual bird can extract and eat about 200 plants per hour and that even a small flock can consume several thousand plants in a feeding session. Corms were typically within 20 mm of the soil surface and were removed primarily by the cockatoo with its beak, but the left foot was sometimes used to excavate the corm from the soil. Flock feeding sessions lasted from about 0.5 to 2.5 hours, but feeding by individual or pairs of birds was often shorter. Plants that had been removed from the soil appeared to have intact corms, but all that was left were the outer scales. Of the plants removed from the soil, only 6% had intact corms attached. The removal of large numbers of Onion Grass plants could impact on their population numbers over time if there was repeated annual harvesting.

Lateralization of vigilance in geese: influence of flock size and distance to the source of disturbance

Left-eye preference, implicating right hemisphere advantage, is typical for vigilant behaviour of many vertebrates. Nevertheless, lateralization of vigilance may be manifested in other ways, such as different reactions to the danger viewed with the right and left eye. Here, we studied one-side biases in the orientation of white-fronted geese Anser albifrons feeding in flocks at different distances to the source of anthropogenic disturbance (a road with traffic) and in flocks of different sizes. The birds which used the left eye to monitor the road were at shorter distances to the road than the birds which used the right eye. The tendency to monitor the road with the right eye decreased with increasing flock size. Trade-offs between feeding, social and vigilant behaviour could explain these tendencies.

Zalecenia dietetyczne dotyczące spożywania jodu — w poszukiwaniu konsensusu między kardiologami a endokrynologami

Iodine is one of the essential bioactive components of a diet and which has an influence on the thyroid hormones synthesis, and these hormones affect the proper development and functioning of the organism. In the situation when the iodides consumption is less than 50 μ g/day, it is unable to maintain the thyroid hormones synthesis at a normal level by the thyroid gland. The 1992/1993 Polish Council for Control of Iodine Deficiency Disorders study results were a direct reason for the compulsory resumption of table salt iodination. Table salt is a, commonly used, iodine carrier. According to the World Health Organization recommendations, the daily salt intake should not exceed 5 g NaCl (2 g Na) per person. Verification of Na content in the diet is a method for cardiovascular diseases prevention. Actions aimed at increasing of the other natural iodine carriers (milk, mineral water) intake are taken. Alternative sources of iodine in the diet are include: codfish, pollock, salmon, eggs, wheat bran, broccoli, dried pea seeds and hazelnuts. Iodination of mineral water and milk, as well as biofortification of the selected vegetables and feeding flock and cattle by food rich in iodine should be concerned according to salt restriction diet.

PSV-6 A survey of New England sheep producers.

Maternal nutrition during gestation impacts offspring BW, body composition, and metabolism, thereby affecting productivity. Several sources of information are available to producers for guidance in managing their breeding flocks; however, it is unknown if sheep producers in New England utilize these resources. In previous USDA surveys of sheep producers, New England was not included, thus leaving a gap of knowledge. Our objective was to conduct a survey of New England sheep producers to determine flock size, breeds, pregnancy detection methods, feeding management practices, and producer learning styles. In particular, we wanted to determine if flock size influenced management practices, and if flock purpose (eg., meat, fiber) and feed type (eg., hay) influenced feed management. A 12-question survey was developed and disseminated via Qualtrics using e-mail survey links, with a 33.2% response rate (n = 96 responses). Data were analyzed using SPSS. Of the respondents, 61.5% had flocks sizes of 11 to 50 sheep. Most producers (63.5%) maintain 1 breed of sheep; however, larger flocks (> 50 sheep) are more likely to maintain multiple breeds (P < 0.05). The majority (79.2%) use their sheep for meat production, 61.5% for fiber, and 37.1% manage sheep for both. Spring (January to May) is the primary (59.4%) lambing season. The majority (76.0%) of New England sheep producers do not analyze their feed, which presents an opportunity for improved outreach. There were correlations (P < 0.05) between flock size and flock purpose, flock size and number of breeds owned, flock size and feed type, feed types and number of feed types used, feed type and feed analysis, and source of feed information. In conclusion, New England sheep producers have flocks of varying size and purpose, and would likely benefit from outreach education on the benefits of diet analysis and formulation for their breeding flocks.

Ten new species of Brueelia Kéler, 1936 (Phthiraptera: Ischnocera: Philopteridae) from nuthatches (Aves: Passeriformes: Sittidae), tits and chickadees (Paridae), and goldcrests (Regulidae).

Ten new species of chewing lice in the genus Brueelia Kéler, 1936, are described from hosts in the families Paridae, Regulidae, and Sittidae. They are: Brueelia johnsoni n. sp. from Poecile sclateri eidos (Peters, 1927); Brueelia juniperi n. sp. from Baeolophus ridgwayi ridgwayi (Richmond, 1902); Brueelia kabulica n. sp. from Sitta tephronota tephronota Sharpe, 1872; Brueelia mpumalangensis n. sp. from Melaniparus niger niger (Vieillot, 1818); Brueelia nazae n. sp. from Parus cinereus caschmirensis Hartert, 1905; Brueelia oxyrhyncha n. sp. from Sitta nagaensis nagaensis Godwin-Austen, 1874; Brueelia picea. sp. from Parus major excelsus Buvry, 1857; Brueelia ragusica n. sp. from Sitta neumayer neumayer Michahelles, 1830; Brueelia regulicida n. sp. from Regulus calendula grinnelli Palmer, 1897; Brueelia sittacola n. sp. from Sitta carolinensis carolinensis Latham, 1790. Brueelia regulicida is the first Brueelia-complex louse to be described from the host family Regulidae. Collectively, the Brueelia of parid, regulid, and sittid hosts show two peculiar patterns. Firstly, lice on closely related hosts appear to be distantly related. Secondly, lice on most hosts in these families appear to be more closely related to lice on other host families than to each other. This contradicts the traditional view that Brueelia-complex lice on closely related hosts are themselves closely related. Potentially, the tendency of the hosts to participate in mixed-species feeding flocks may explain some of these patterns.

Feeding flocks on rangelands: insights into the local ecological knowledge of shepherds in Boulemane province (Morocco)

In Mediterranean regions, traditional pastoral systems involve shepherds leading flocks along daily grazing circuits on arid rangelands. Over the past decades, these systems have become increasingly agro-pastoral and the importance given to feeding flocks on rangelands is variable. Our study aimed at investigating the local ecological knowledge (LEK) about forage plants and animal foraging behaviour of shepherds in a pastoral area of Morocco, and eventually analysing the possible interactions between such LEK, its utilisation for grazing management and the pastoral status of the farm. Eleven semi-directive interviews with shepherds, either salaried or owning their own farm, were carried out at three sites differing in terms of agricultural context and available forage resources. Shepherds’ LEK included recognising and naming forage plants and rangeland types, identifying preferred or less preferred plants or plant parts, describing circumstantial palatability of plants depending mainly on season, other locally available plants and watering times. LEK about animal feeding preferences and its integration into grazing management was more extensive at sites where pastoral systems were still most valued, and for shepherds who were either experienced or who were considering the activity in the future. Conversely, young salaried shepherds or farmer-shepherds who devoted more attention to the agricultural component of their system seemed to be less knowledgeable about the subject. In a context where pastoralism is challenged both by the higher profitability of agriculture and by the depletion of pastoral resources as a result of frequent droughts and decreased surface area devoted to grazing lands, the future of such LEK is uncertain. The perpetuation of LEK might depend on the ability of local extension services to value farmers’ LEK and to help them enrich it with scientific knowledge.

Environmental characteristics of shallow bottoms used by Greater FlamingoPhoenicopterus roseusin a northern Adriatic lagoon

AbstractSince the beginning of this century, Greater FlamingoPhoenicopterus roseusflocks have been observed regularly when feeding in the large extensions of shallow bottoms in the Lagoon of Venice (NE Italy), the largest lagoon along the Mediterranean. Nowadays thousands of flamingos are present throughout the year. Between 2013 and 2017 I collected data on the environmental features of the shallow bottoms used by feeding flocks, along with measurements of flight initiation distance (FID) of Greater Flamingo in response to the approach of boats and pedestrians. Shallow bottoms were shown to be used when covered with approximately 10 to 60 cm of water. All the feeding sites were in open landscapes, with low occurrence of saltmarshes in a radius of 500 m. The bottoms were barely covered with seagrasses (&lt;4% of the surface around the survey points) and were mostly silty. Feeding flocks were on average 1.2 km far from the nearest road or dyke, while the mean distance from channels that could be used by boats was about 420 m. The mean FID caused by boats or pedestrians was 241 m ± 117 m (N = 31, ± 1 SD) without significant differences between those for the two disturbance sources. The use of shallow bottoms by the Greater Flamingo appears governed primarily by the tidal cycle, but boat disturbance probably modifies this effect. According to FID values, a set-back distance of 465 m is suggested to reduce the disturbance caused by boats and pedestrians to the flamingo feeding flocks.

Positive Interactions among Foraging Seabirds, Marine Mammals and Fishes and Implications for Their Conservation

There is increasing recognition of the importance of “positive interactions” among species in structuring communities. For seabirds, an important kind of positive interaction is the use of birds of the same species, birds of other species, and other marine predators such as cetaceans, seals and fishes as cues to the presence of prey. The process by which a single bird uses, say, a feeding flock of birds as a cue to the presence of prey is called “local enhancement” or “facilitation”. There are subtly different uses of each of these terms, but the issue we address here is the ubiquity of positive interactions between seabirds and other marine predators when foraging at sea, and whether as a result of their associations the feeding success, and therefore presumably the fitness, of individual seabirds is increased. If this contention is true, then it implies that conservation of any one species of seabird must take into consideration the status and possible conservation of those species that the focal species uses as a cue while foraging. For example, conservation of great shearwaters (Ardenna gravis), which often feed over tuna (e.g. Thunnus) schools, should take in to consideration conservation of tuna. Ecosystem management depends on understanding the importance of such processes; the loss of biodiversity, and the consequent threat to foraging success, may be a substantial threat to the stability of marine ecosystems.

Food Availability But Not Sex Determines Morning Foraging Area Size in the Great Bustard Otis tarda, the Most Sexually Size-Dimorphic Bird Species

Summary. Sexual size dimorphism (SSD) may favour physiological peculiarities in diet, behaviour and home-range size both across species and within species. Sex-specific differences in diet and behaviour have been reported in several bird species but there are fewer studies of foraging area size in sexually dimorphic bird species. Foraging area size should be greater in the bigger sex according to home-range size predictions based on body mass. We tested this prediction in a winter study of foraging area size in the Great Bustard Otis tarda, the most sexually size-dimorphic bird species, which forages in unisexual flocks. In this species the temporal pattern of a flock's feeding intensity; the proportion of birds actively feeding (FI) and the size of the morning foraging area (MFA) of each sex are unknown. We recorded the behaviour and movements of unisexual flocks of Great Bustards during winter mornings and sampled food availability to take into account its effect on FI and MFA. FI increased and then dec...

Profitability Assessment of Sheep Farming Under Field Conditions in Temperate Himalayan Climate of Jammu and Kashmir

Present study was conducted in the hilly district of Bandipora of Jammu and Kashmir. The district was divided into low-lying (Sonawari), medium altitude (Bandipora) and High altitude (Gurez) regions. A total of 477 respondents were considered for the survey. Information on varied aspects of sheep economics was sought from the respondents (sheep rearers) based on a pre-tested questionnaire. The total annual expenditure for 19 ewes and followers under prevailing production system was Rs 75083.63 while it was Rs 153032.24, Rs 291480.5 for a sheep unit of 34 ewes and 1 ram, 63 ewes and 2 rams, respectively. Cost of feeding was the major cost component representing more than 70% of total expenditure. Profitability increased with increase in flock size. Under prevailing production system, a sheep unit consisting of 63 ewes and 2 rams was more profitable than sheep units with lower flock size. Net income/year and net income/animal/year was highest in Sonawari followed by Bandipora and least in Gurez region. Present study showed that annual returns on sheep production increase with increase in flock size and feeding expenses represent the single largest component of expenditure on sheep rearing. Further, a sheep unit of 60 above flock size is more or less sufficient to sustain a medium sized family under prevailing production system.

Spatial patterns of seasonal distribution of Corvidae (the case of urban habitats)

Corvids in Zhytomyr city reach maximum density in the winter period. Rooks and Eurasian Jackdaws were the most abundant species in winter, usually feeding in multispecies flocks and forming collective roosts.Suburban green areas (buffer zones) were characterized by a considerably high diversity of Corvidae species: this habitat was occupied by all six species. We also registered the highest density of Eurasian Jays and Hooded Crows in this habitat. The green areas in the city center were also characterized by significant corvid density, especially during the breeding season. The maximum breeding density of Rooks was in these habitats, which held 6 of 12 identified urban colonies in Zhytomyr. We found that the European Magpies, Eurasian Jays, and Hooded Crows also had high breeding success here. Eurasian Jackdaws occurred here only in autumn and winter, when they fed together with Rooks on lawns, gardens, and parks. With stable snow cover the Rook density in habitats of the green areas decreased due to the depletion of food resources.The individual buildings zone of the city were characterized by the lowest density of all corvid species, except for European Magpies and Eurasian Jays. The number of common species (Rooks, Eurasian Jackdaws, and Hooded Crows) was low because of shortage of food resources, lack of sites for large roosting flocks and shortage of suitable nesting sites. However, Eurasian Magpies reached one of their highest densities in this habitat (12.8 birds/km2). This species was registered in habitats around private buildings all the year round, successfully nesting in the yards of private houses and on trees in the streets. Its breeding density was 11.2 birds/km2.During three years of research (2009–2012) the density of all corvids except for European Magpie, practically did not change, although we determined a slight positive trend for all the species. The strong increase in the number of Eurasian Jackdaws could be explained by the increasing density of wintering populations or due to the increasing number of migrants from more northern regions.

A Kleptoparasitic Chase by Brown Pelicans on a Western Gull

interspecific kleptoparasitism, or the stealing of food from other species, is fairly widespread among birds, most frequently reported for seabirds, especially among the Charadriiformes (Brockman and Barnard 1979, Furness 1987, iyengar 2008). Though most kleptoparasitic species engage in this behavior facultatively, some (especially within the Charadriiformes) may be obligate kleptoparasites during a particular season and potentially throughout the year (iyengar 2008). Within the family Pelecanidae it has been infrequently reported in the literature. The ecology and behavior of seabirds meet many of the ecological factors proposed for the evolution of kleptoparasitism, including open habitat, feeding in mixed-species groups, scavenging, and the host’s habits being predictable (Brockman and Barnard 1979, Paulson 1985, iyengar 2008). Though kleptoparasitism often involves a larger species stealing food from a smaller species, the Brown Pelican (Pelecanus occidentalis) is perhaps better known as the victim of kleptoparasitism by smaller gulls than vice versa, with several species of gulls and terns reported to steal from it (Shields 2014). The Brown Pelican was the first species of pelican reported to kleptoparasitize (Sefton 1950, Brockmann and Barnard 1979), and this behavior has since been reported in the americas by the closely related Peruvian Pelican (P. thagus) (Duffy 1980) and the american White Pelican (P. erythrorhynchos) (O’malley and evans 1983, anderson 1991). reports of kleptoparasitic attacks by the Brown Pelican have appeared to be isolated incidents. in the Peruvian Pelican, however, Duffy (1983) reported that 18% of attempts to obtain prey involved piracy. most reported kleptoparasitic attacks by the Brown Pelican and closely related Peruvian Pelican have been in mixed feeding flocks where the pelican is sitting on the water and grabs with its bill or otherwise attacks a nearby species, getting it to drop its food (Sefton 1950, Duffy 1980, lanciani 2000). This is especially common in situations where the birds are feeding on offal being thrown by people, though it occurs regularly in “wild” situations as well (D. anderson pers. comm.). The Brown Pelican’s target species have included the Double-crested Cormorant (Phalacrocorax auritus) and unidentified gulls (Larus spp.), as well as other Brown Pelicans (D. anderson pers. comm.). Brown Pelicans have also been observed landing on Great Blue Herons (Ardea herodias) in order to get them to drop food (Bildstein 1980). O’malley and evans (1983) observed aerial chases by american White Pelicans in pursuit of food, but i am aware of no such observations involving the Brown Pelican. at ~16:30 on 19 October 2013, during an organized whale watch out of long Beach, California, in the vicinity of Platform ellen (Orange County), i noted a subadult (second-cycle) Western Gull (L. occidentalis) chasing an adult Western Gull, followed by two adult Brown Pelicans. The four birds were first seen flying parallel to the boat, about a kilometer away and only a few meters above the water. The second-cycle Western Gull was close behind the adult Western Gull with the two pelicans following about three meters behind the gulls. The adult gull banked up at roughly a 45° angle to a height of about 5 meters above the water before gliding back down in an attempt to escape. The second-cycle gull followed closely, and the pelicans also followed, banking up behind the gulls. The lead gull reversed course and quickly made a sharp ascent; through labored flight the pelicans were able to follow. While the second-cycle gull was able to stay on the tail of the lead gull, the pelicans fell back to about 10 meters behind both gulls. However, when the lead gull reversed course again, flying low over the water, both pelicans were able to shorten the gap and eventually overtake the second-cycle gull, placing nOTeS

Meadow up a tree: Feeding flocks with a native ash tree in the Moroccan mountains

The pastoral interest in Fraxinus dimorpha foliage from the High Atlas of Morocco was assessed both in terms of its role with regard to the feeding of small ruminant flocks and for its nutritive value. Observation, measurements, and interviews with 57 households revealed that ash trees are regularly pollarded, following very precise four-year cycles, during late August to November. Native ash tree stands are subject to characteristic shaping, which enables a continuous capability to provide fodder, and gives rise to characteristic sylvo-pastoral landscapes. A digestion trial was conducted in goats and sheep. Five two-year-old rams (19.5 ± 1 kg) and five two-year-old uncastrated bucks (22.2 ± 1.7 kg) were placed in individual metabolism cages over 18 days, and fed fresh ash tree leaves with a light dietary supplementation. The apparent digestibility coefficients between goats and sheep did not differ significantly for dry matter (69.5% versus 67.5%, respectively), organic matter (70.5% vs 68.3%), and Neutral Detergent Fibre (53.8% vs 52.3%), in contrast to crude protein (54.2% vs 45.3%, p < 0.001) and Acid Detergent Lignin (29.7 vs 26.4, p < 0.05). Due to a higher intake relative to metabolic weight (57.1 vs 47.7 gDM/kgBW0.75), goats valorize this type of forage better than sheep. It is concluded that ash tree foliage presents considerable nutritive interest in autumn when overall range forage is scarce and lacking in quality, and, hence, constitutes a useful forage resource for feeding the small ruminant flocks found in these low-input mountain livestock farming systems. Associated traditional management practices were revealed to be both technically and ecologically efficient, and should be better taken into account by policy-makers.

Flocking Behavior of Shiny Cowbirds (Molothrus bonariensis) At Feeding Areas During the Daily Cycle

ABSTRACT The social systems and space use of birds depend on the distribution and abundance of resources. Brood-parasitic cowbirds (Molothrus spp.) exhibit a unique pattern of changing social behavior on a daily cycle. Female Brown-headed Cowbirds (M. ater) in North America spend the morning accompanied by males searching for host nests, and in the afternoon both sexes join feeding flocks. We studied flocking patterns of Shiny Cowbirds (M. bonariensis) in open-habitat animal exhibits at a zoo in Colombia. Flock sizes of both males and females were low in the morning but increased towards noon. Male abundance remained high during the afternoon, but female abundance was very variable. Numbers of juveniles did not change throughout the day. This is consistent with the idea that cowbirds are spread out during the morning in the breeding areas and aggregate in the afternoon to feed. Cowbirds change their social behavior on a daily basis in response to the different pressures of their breeding and feeding ecolo...