scholarly journals Foraging behavior and at-sea distribution of White-Tailed Tropicbirds in tropical ocean

2017 ◽  
Vol 78 (3) ◽  
pp. 556-563 ◽  
Author(s):  
L. F. A. S. Campos ◽  
A. B. Andrade ◽  
S. Bertrand ◽  
M. A. Efe
Keyword(s):  
Endangered Species ◽  
Foraging Behavior ◽  
Mortality Rates ◽  
Nest Attendance ◽  
Breeding Colony ◽  
Tropical Ocean ◽  
Foraging Patterns ◽  
Land Crab ◽  
Egg Consumption ◽  
Foraging Pattern

Abstract We used miniaturized GPS loggers and site observations to access foraging patterns and nest behaviour of the White-tailed Tropicbird Phaethon lepturus (WTTB), an endangered species at its South Atlantic breeding colony. Dual foraging pattern was observed with alternation between long and short foraging trips. Birds responsible for nest attendance engaged in short foraging trips with mean distance from colony of 25 ± 17 km, total distance covered of 79 ± 65 km and mean duration of 4.02 ± 5.28 hours. Birds flew by dawn and returned before dusk while partners were at sea for long foraging trips that ranged from four to 11 days, with mean maximum distance from colony of 105 ± 47.48 km. Chicks were usually left alone for hours and chick predation by Land Crab Johngartia lagostroma, egg consumption by Goniopsis cruentata and intra-specific competition are suspected to be responsible for high chick mortality rates.

Observations on the Flight Patterns and Foraging Behavior of Tasmanian Bats

1986 ◽  
Vol 13 (3) ◽  
pp. 427 ◽  
Author(s):  
MG Oneill ◽  
RJ Taylor
Keyword(s):  
Foraging Behavior ◽  
Foraging Behaviour ◽  
Foraging Patterns ◽  
Broad Agreement ◽  
Direct Flight

Observations were made on the flight patterns and foraging behaviour of Tasmanian bat species, by the use of light tags and the release of individuals at dusk while it was still light enough to see clearly. Four distinct foraging patterns were observed, each being characteristic of a pair of species. These pairs were: Nyctophrlusgeoffroyi and N. timoriensis (slowest flight, undulating, closest to vegetation); Eptesicus vulturnus and E. regulus (highly manoeuvrable, faster than Nyctophilus, further from vegetation); E. sagittula and Chalinolobus morio (fast, direct flight, less manoeuvrable than smaller Eptesicus and fly higher); and Pipistrellus tasmaniensis and C. gouldii (faster, most direct flight, limited manoeuvrability, prefer open areas). There is a broad agreement between the flight patterns observed and the relative shape of the wing of each species.

scholarly journals Provisioning Rate and Attendance Patterns of Wandering Albatrosses at Bird Island, South Georgia

The Condor ◽  
2001 ◽  
Vol 103 (2) ◽  
pp. 230-239 ◽  
Author(s):  
Simon D. Berrow ◽  
John P. Croxall
Keyword(s):  
Foraging Behavior ◽  
Body Mass ◽  
Work Rate ◽  
Meal Size ◽  
Trip Duration ◽  
Foraging Patterns ◽  
South Georgia ◽  
Diomedea Exulans ◽  
Attendance Patterns ◽  
Provisioning Rate

Abstract We investigated foraging behavior of Wandering Albatrosses (Diomedea exulans) breeding at South Georgia to assess how sex and season-specific foraging patterns relate to provisioning performance. We estimated Wandering Albatross chicks require 60–65 kg of food over the chick-rearing period; males deliver 54% of this total. Meal size delivered by both sexes remained essentially constant throughout the post-brooding chick-rearing period, but foraging trip duration varied considerably. Females made consistently longer foraging trips and delivered smaller meals but transported an average load that was 20% heavier in proportion to their body mass than males. We suggest that chick-rearing places greater demands on females compared with males and Wandering Albatrosses work hard to deliver food during the first half of chick rearing (at the expense of their own condition), thereafter reduce their work rate, presumably so as not to compromise their survival.

scholarly journals Aggressive Nest Intrusions by Male Humboldt Penguins

The Condor ◽  
2001 ◽  
Vol 103 (1) ◽  
pp. 162-165 ◽  
Author(s):  
Sabrina S. Taylor ◽  
Marty L. Leonard ◽  
Daryl J. Boness
Keyword(s):  
Endangered Species ◽  
Population Recovery ◽  
Breeding Colony ◽  
Aggressive Interactions ◽  
Breeding Failure

Abstract During observations at a breeding colony of Humboldt Penguins (Spheniscus humboldti), we noted five male penguins enter nests occupied by breeding pairs and engage in aggressive interactions with the resident adult. These nest intrusions resulted in egg loss or infanticide, and accounted for 11.1% of breeding failure in the colony. Two intruder males ultimately mated with respective resident females. This behavior had not been observed previously in Humboldt Penguins and we suggest that it may occur when males are unable to obtain mates through advertising at the nest. Intrusion behavior may slow down population recovery in this endangered species.

Foraging patterns of Water Pipits (Anthus spinoletta) with nestlings

1987 ◽  
Vol 65 (6) ◽  
pp. 1522-1529 ◽  
Author(s):  
Paul Hendricks
Keyword(s):  
Foraging Behavior ◽  
Energy Efficient ◽  
Niche Partitioning ◽  
Delivery Rate ◽  
Female Dominance ◽  
Behavior Changes ◽  
Foraging Patterns ◽  
Trade Off ◽  
Alpine Habitat ◽  
Nest Distribution

Foraging patterns of pairs of Water Pipits (Anthus spinoletta) nesting in alpine habitat in Wyoming were examined for sex-specific differences in division of space, how foraging behavior changes with nestling age, and how foraging behavior is modified to reduce the risk of nest detection by predators. Parental investment (measured by number of deliveries to nestlings, fecal sac removal, and time spent incubating and brooding) was not useful in predicting patterns of sexual niche partitioning of foraging space. There were no consistent patterns as to which sex foraged farthest from the nest. Distribution of the orientation of trip departures from nests, however, was significantly different between pair members in all cases. The mechanism(s) maintaining this pattern of spatial segregation is not known, but it may be the result of female dominance during the breeding season. Delivery rate of food to nestlings was positively correlated to nestling age. There was a concurrent positive correlation between delivery rate and percentage of foraging trips less than 50 m from the nest. Adult pipits flew significantly longer distances from nests when departing with fecal sacs. This is probably an adaptation to reduce the probability of nest detection by predators, and represents a trade-off between energy-efficient foraging and reproductive success.

scholarly journals A Novel Plant Root Foraging Algorithm for Image Segmentation Problems

2014 ◽  
Vol 2014 ◽  
pp. 1-16 ◽  
Author(s):  
Lianbo Ma ◽  
Kunyuan Hu ◽  
Yunlong Zhu ◽  
Hanning Chen ◽  
Maowei He
Keyword(s):  
Image Segmentation ◽  
Foraging Behavior ◽  
Plant Root ◽  
Biologically Inspired ◽  
Foraging Patterns ◽  
Root Foraging ◽  
New Type ◽  
Optimization Methodology ◽  
Multimodal Problems ◽  
Segmentation Problem

This paper presents a new type of biologically-inspired global optimization methodology for image segmentation based on plant root foraging behavior, namely, artificial root foraging algorithm (ARFO). The essential motive of ARFO is to imitate the significant characteristics of plant root foraging behavior including branching, regrowing, and tropisms for constructing a heuristic algorithm for multidimensional and multimodal problems. A mathematical model is firstly designed to abstract various plant root foraging patterns. Then, the basic process of ARFO algorithm derived in the model is described in details. When tested against ten benchmark functions, ARFO shows the superiority to other state-of-the-art algorithms on several benchmark functions. Further, we employed the ARFO algorithm to deal with multilevel threshold image segmentation problem. Experimental results of the new algorithm on a variety of images demonstrated the suitability of the proposed method for solving such problem.

scholarly journals Variasi Pola Mencari Makan Tiga Jenis Kuntul di Sekitar Cagar Alam Pulau Dua Serang, Propinsi Banten

2011 ◽  
Vol 1 (2) ◽  
pp. 54
Author(s):  
Dewi Elfidasari
Keyword(s):  
Sampling Method ◽  
Rice Field ◽  
Foraging Patterns ◽  
Pattern Type ◽  
Bubulcus Ibis ◽  
Type Pattern ◽  
Feeding Area ◽  
Focal Observation ◽  
Foraging Pattern ◽  
Egretta Garzetta

<p>Variasi pola mencari makan dari tiga jenis kuntul yang menghuni Cagar Alam Pulau Dua telah diamati selama 12 bulan. Penelitian dilakukan di lokasi makan dari ketiga jenis kuntul yang berada di sekitar kawasan Cagar Alam Pulau Dua. Metode penelitian yang digunakan adalah pengamatan langsung dengan didukung oleh pengambilan gambar menggunakan Handycam dengan metode <em>Focal Observation</em>. Hasil penelitian ini menunjukkan bahwa pola mencari makan pada <em>Casmerodius albus</em> adalah sebanyak 30 pola, variasi pola tertinggi dijumpai pada sawah di waktu pagi (17 pola), dan pola mencari makan yang paling sering dilakukan adalah PCa1. Pola mencari makan <em>Egretta garzetta</em> meliputi 160 variasi tertinggi dijumpai pada lokasi makan dataran lumpur pada waktu pagi (47 macam pola), dan macam pola dengan frekuensi tertinggi adalah PEg1. Sedangkan pada <em>Bubulcus ibis</em>, pola mencari makan yang ditemukan adalah sebanyak 65 jenis, dengan variasi tertinggi dijumpai pada sawah di waktu pagi (33 pola) dan pola mencari makan dengan frekuensi tertinggi adalah PBi15.</p><h6 style="text-align: center;"><strong>Abstract</strong></h6><p>Foraging pattern variation of  three herons species living in Pulau Dua Nature reserve Serang, Banten Province was observed to 12 months. Research was conducted  done at feeding area of three species of herons around Cagar Alam Pulau Dua. The research method was a combination of direct observation and “focal sampling” method using videotape (handycam). The result showed that foraging pattern of <em>Casmerodius albus </em>were as much 30 kinds, supreme pattern variation was found on the rice-field in the morning (17 type pattern), and the coming foraging pattern was PCa1. Foraging patterns in <em>Egretta garzetta </em>were 160 types, supreme variation to be met on mudflat in the morning (47 type pattern), and pattern type with supreme frequency was PEg1. However on the <em>Bubulcus ibis </em>, the number of foraging pattern were as much 65 types, with supreme variation found on rice-field in the morning (33 type pattern) and pattern type with supreme frequency was PBi15.</p>

scholarly journals The sedge Carex secalina – critically endangered species in Poland: new locality in the breeding colony of black-headed gull Chroicocephalus ridibundus

2016 ◽  
Vol 42 (1) ◽  
pp. 27-31
Author(s):  
Rafał Sandecki
Keyword(s):  
Endangered Species ◽  
Population Size ◽  
Critically Endangered ◽  
Breeding Colony ◽  
Critically Endangered Species ◽  
Nesting Material

Abstract A new locality of rye sedge Carex secalina, a critically endangered species was discovered on an island of Lake Kusowo, in the vicinity of Bydgoszcz (Kuyavian-Pomeranian Province), in June 2015. The species was found in a breeding colony of black-headed gull Chroicocephalus ridibundus. The population size was estimated at least at 30 individuals and all of them produced generative shoots. This locality of C. secalina is the northernmost in Poland and the only ascertained, apart from Inowrocław Plain. Colonization of the island by C. secalina was caused, probably, by zoochory as a result of accidental bringing of propagules by gulls, together with nesting material from outside the colony.

The foraging behavior of a generalist feeder, the central mudminnow (Umbra limi)

1984 ◽  
Vol 62 (3) ◽  
pp. 457-462 ◽  
Author(s):  
Cynthia A. Paszkowski
Keyword(s):  
Water Column ◽  
Foraging Behavior ◽  
Significant Variation ◽  
Laboratory Experiments ◽  
Submerged Macrophytes ◽  
Foraging Success ◽  
Foraging Patterns ◽  
Natural Diet ◽  
Use Patterns ◽  
Bottom Substrate

The natural diet and habitat use patterns of the central mudminnow suggest that it is a generalist feeder capable of using a variety of foraging sites. Laboratory experiments were performed to measure the efficiency of this species as it foraged from four sites: open bottom substrate, the water column, submerged macrophytes, and the water's surface. Midwater, macrophyte, and surface foraging rates did not differ significantly from each other, whereas bottom rates were somewhat lower. Foraging success was also unaffected by small changes in the experimental environment. Significant variation existed among the foraging patterns of individual fish. The observed versatility of the mudminnow's foraging behavior could aid this species in exploiting physically severe, variable, unproductive, and (or) species-poor environments.

Foraging patterns of California sea otters as indicated by telemetry

1995 ◽  
Vol 73 (3) ◽  
pp. 523-531 ◽  
Author(s):  
Katherine Ralls ◽  
Brian B. Hatfield ◽  
Donald B. Siniff
Keyword(s):  
Foraging Behavior ◽  
Prey Size ◽  
Prey Type ◽  
Dive Duration ◽  
Enhydra Lutris ◽  
Sea Otters ◽  
Foraging Patterns ◽  
Radio Transmitters ◽  
Males And Females ◽  
Juvenile Males

Foraging behavior was studied in 38 sea otters (Enhydra lutris) implanted with radio transmitters. The observed foraging behavior of instrumented individuals was similar to that of uninstrumented otters observed in previous studies: dive duration varied with prey type but not with prey size, dive success was highest for small prey, and the length of surface intervals increased with prey size. However, telemetry revealed that some otters foraged farther offshore and made longer dives than was indicated by visual observations. Individuals within age–sex classes varied in several aspects of foraging behavior, including the duration of dives and length of surface intervals. There were no overall differences between the dive durations or surface intervals during the day and during the night, though some individuals had longer dives or surface intervals during either the day or the night. There were differences in the foraging behavior of the various age–sex classes, the most striking being those between juvenile males and females. Juvenile males foraged much farther offshore [Formula: see text] in deeper water [Formula: see text] than other otters and made long dives during both the day [Formula: see text] and the night [Formula: see text]. Juvenile females fed for longer periods than other otters.

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