Seasonal Changes of Oxygen Consumption in Captive Great Cormorants (Phalacrocorax carbo)

The primary purpose of this study was to compare seasonal changes in cycling gross efficiency (GE) and economy (EC) with changes in other aerobic fitness indices. The secondary aim was to assess the relationship between maximum oxygen consumption, GE, and EC among elite cyclists. The relationships of maximum oxygen consumption with GE and EC were studied in 13 cyclists (8 professional road cyclists and 5 mountain bikers). Seasonal changes in GE and EC, predicted time to exhaustion (pTE), maximum oxygen consumption, and respiratory compensation point (RCP) were examined in a subgroup of 8 subjects, before (TREST) and after (TPRECOMP) the pre-competitive winter training, and during the competitive period (TCOMP). GE and EC were assessed during a constant power test at 75% of peak power output (PPO). Significant main effect for time was found for maximum oxygen consumption (4.623 ± 0.675, 4.879 ± 0.727, and 5.010 ± 0.663 L·min–1; p = 0.028), PPO (417.8 ± 46.5, 443.0 ± 48.0, and 455 ± 48 W; p < 0.001), oxygen uptake at RCP (3.866 ± 0.793, 4.041 ± 0.685, and 4.143 ± 0.643 L·min–1; p = 0.049), power output at RCP (330 ± 64, 354 ± 52, and 361 ± 50 W; p < 0.001), and pTE (17 ± 4, 30 ± 8, and 46 ± 17 min; p < 0.001). No significant main effect for time was found in GE (p = 0.097) or EC (p = 0.225), despite within-subject seasonal changes. No significant correlations were found between absolute maximum oxygen consumption and GE (r = –0.276; p = 0.359) or EC (r = –0.328; p = 0.272). However, cyclists with high maximum oxygen consumption values (i.e., over 80 mL·kg–1·min–1), showed low efficiency rates. Despite within-subject seasonal waves in cycling efficiency, changes in GE and EC should not be expected as direct consequence of changes in other maximal and submaximal parameters of aerobic fitness (i.e., maximum oxygen consumption and RCP).

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Nesting of Great Cormorants (Phalacrocorax carbo) on man-made structures in Ukraine

Biosystems Diversity ◽

10.15421/011640 ◽

2016 ◽

Vol 24 (2) ◽

Author(s):

A. I. Sidorenko ◽

V. D. Siokhin

Keyword(s):

National Level ◽

Field Work ◽

Current Data ◽

Great Cormorant ◽

Phalacrocorax Carbo ◽

Breeding Sites ◽

Breeding Territory ◽

Wide Range ◽

Maintenance Work ◽

Great Cormorants

In Ukraine the Great Cormorant (Phalacrocorax carbo Linnaeus, 1758) uses a rather wide range of habitats for nesting: islands, trees and shrubs, reedbeds and a variety of man-made structures. In general, the strategy of nesting on man-made structures is uncommon both in Ukraine and Europe, and Cormorantsdo this only in the absence of other sites suitable for nesting. Special research onCormorant colonies on technogenic constructions was carried out during the field expeditions by the Research Institute of Biodiversity of Terrestrial and Aquatic Ecosystems of Ukraine in 2002–2003 and 2012–2016. Besides this, we used retrospective and current data from the literature and Internet resources. Most of the field work was carried out by making surveys by boat and on foot. As a result, we found 8 Cormorant colonies on technogenic constructions in Ukraine: gas platforms in the Sea of Azov (near the village Strilkove, Henichesk district of Kherson region); sunken ships – targets for bombing training near the Arabat Spit (these are also known as «ship islands»); electricity pylons of the high-voltage Enerhodar Dnipro Power Line where it crosses the Kakhovka Reservoir; the dock in Yahorlyk Bayk, used in the past as a target for bombing training bombing; artificial island-platforms on Lake Chernine (Kinburn Peninsula); an artificial island on the Sasyk Lagoon (Odessa region); artificial islands, made as navigation markers on the Kremenchuk and Kiev reservoirs. The study found that in most cases the accompanying species was the CaspianGull (Larus cachinnans Pallas, 1811), which actively destroys the Cormorants’ nests and eats their eggs and chicks. The number of nests in the colonies varied greatly (5–30 nests on the navigation marker islands and ca. 2 000–2 300 on the «ship-islands» and gas platforms). This is due, primarily, to the area of the breeding territory. The research found that fierce territorial competition was observed in most of the colonies both with Caspian Gulls and between Cormorants. In addition, we observed anthropogenic interference in the colonies by fishermen and workers conducting routine maintenance work (as happened in the case of electricity pylons and gas platforms). The benefit of this study is that it is the first research in Ukraine conducted at national level onthis type of nesting by Cormorants. Moreover, the study examines the history of emergence of these nesting territories and population dynamics of the Great Cormorant from the time of initial settlement of the breeding sites till the present.

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Flock-fishing deep-diving piscivores (Great Crested Grebe Podiceps cristatus, Great Cormorant Phalacrocorax carbo, Common Merganser Mergus merganser) at Lake Vombsjön, southern Sweden, and those that exploit them

Ornis Svecica ◽

10.34080/os.v28.19520 ◽

2018 ◽

Vol 28 (1) ◽

Author(s):

Hans Källander

Keyword(s):

Great Cormorant ◽

Southern Sweden ◽

Phalacrocorax Carbo ◽

Herring Gulls ◽

Deep Diving ◽

Large Numbers ◽

Ardea Cinerea ◽

Mergus Merganser ◽

Podiceps Cristatus ◽

Great Cormorants

Lake Vombsjön in southern Sweden is visited by large numbers of Great Crested Grebes Podiceps cristatus (>2000), Great Cormorants Phalacrocorax carbo (sometimes >1000) and Common Mergansers Mergus merganser (up to 2000) in late autumn and early winter. Different species exploit them. Great Crested Grebes are used especially by commensal Common Gulls Larus canus; the gulls take advantage of fish that flee towards the surface. Common Gulls also use cormorants and mergansers in the same way but also try to kleptoparasitize them. Both Herring Gulls Larus argentatus and Great Black-backed Gulls Larus marinus kleptoparasitize these two species, while Red Kites Milvus milvus, Grey Herons Ardea cinerea and Carrion Crows Corvus corone use them commensally. White-tailed Eagles Haliaeetus albicilla seem to use both methods to obtain fish. On 50% of one hundred visits during November to March, eagles were seen flying low over the fishing flocks. They would fly a metre or so above the flocks and then accelerate and attack a bird holding a fish. The bird would then either try to escape by a rush or by diving, dropping the fish which the eagle seized. Interestingly, the flock-fishing birds showed no fear reactions towards the eagles but appeared to regard them similarly to large gulls.

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Great cormorant (Phalacrocorax carbo) predation on pikeperch (Sander lucioperca L.) in shallow eutrophic lakes in Poland

Archives of Polish Fisheries ◽

10.1515/aopf-2017-0012 ◽

2017 ◽

Vol 25 (2) ◽

pp. 123-130 ◽

Cited By ~ 1

Author(s):

Piotr Traczuk ◽

Andrzej Kapusta

Keyword(s):

Length Distribution ◽

Bird Species ◽

Fish Populations ◽

Great Cormorant ◽

Phalacrocorax Carbo ◽

Sander Lucioperca ◽

Eutrophic Lakes ◽

Breeding Colony ◽

Great Cormorants

AbstractIncreases in the population abundance of the piscivorous great cormorant (Phalacrocorax carbo) has led to conflicts with fisheries. Cormorants are blamed for decreased fish catches in many lakes in Poland. The aim of this paper is to describe to role of pikeperch (Sander lucioperca) in the diet of cormorants nesting in a colony on the island in Lake Warnołty. Since the breeding colony is located in the vicinity of Lake OEniardwy, the largest lake in Poland, the cormorants use the resources in this lake. In 2009-2016, 18,432 regurgitated fish were collected, of which 593 were pikeperch. The share of pikeperch among fish collected in 2009-2012 did not exceed 2%, but from 2013 this increased substantially to maximum of 38.2% in 2015. The smallest pikeperch had a standard length of 8.4 cm, and the largest 42.5 cm. Pikeperch mean length differed by year, and the length distribution was close to normal. The sizes of the regurgitated pikeperch indicate that cormorants prey almost exclusively on juvenile specimens. The results of the present study indicate that cormorant predation has a significant impact on pikeperch populations in lakes in the vicinity of the colony, and the great cormorants are possibly a significant factor in the effectiveness of pikeperch management. When planning for the management of fish populations in lakes subjected to cormorant predation pressure, it should be borne in mind that predation by this piscivorous bird species impacts the abundance and size-age structure of fish populations.

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Levels of infection of gastric nematodes in a flock of great cormorants (Phalacrocorax carbo) from Lake Biwa, Japan

Journal of Helminthology ◽

10.1017/s0022149x11000046 ◽

2011 ◽

Vol 86 (1) ◽

pp. 54-63 ◽

Cited By ~ 10

Author(s):

Kh.M. El-Dakhly ◽

E. El-Nahass ◽

S. Uni ◽

H. Tuji ◽

H. Sakai ◽

...

Keyword(s):

Lake Biwa ◽

Single Species ◽

Phalacrocorax Carbo ◽

Connective Tissues ◽

Inflammatory Reactions ◽

Large Numbers ◽

Mucosal Surfaces ◽

Contracaecum Rudolphii ◽

High Prevalence ◽

Great Cormorants

AbstractA high prevalence (86.7%) of various species of nematodes was observed in the stomach of great cormorants living in Lake Biwa, Japan. There were varying numbers of adults belonging to two common genera, Eustrongylides Jagerskiold 1909 (Nematoda: Dioctophymatidae) and Contracaecum Railliet & Henry 1912 (Nematoda: Anisakidae). The first included common adenophorean nematodes comprising a single species, Eustrongylides tubifex and the second comprised ascaroid nematodes that contained four named species: Contracaecum rudolphii Hartwich, 1964, Contracaecum microcephalum Yamaguti, 1961, Contracaecum multipapillatum Drasche, 1882 and Contracaecum chubutensis Garbin, 2008. After the prevalence and intensity of the infection had been noted, both types of nematodes were frequently observed to penetrate the mucosa and intrude into the wall of the glandular stomach, where they caused gross haemorrhage and ulceration. The Eustrongylides sp. was predominantly found in a nodular lesion of the proventricular wall, while Contracaecum spp. were observed either free in the lumen of the proventriculus or, on occasion, deeply penetrating its wall. Of the Contracaecum spp., C. rudolphii was the most prevalent. Grossly, large numbers of nematodes were present in infected stomachs (for C. rudolphii intensity was 1–34 and 3–57 nematodes in male birds and 1–21 and 1–32 in females; for C. microcephalum 1–2 and 1 in male birds and 1–2 in females; for C. multipapillatum 2 in male cormorants and no infection in females; for C. chubutensis 1–2 and 1 in male birds and 1–5 and 1 in females and for E. tubifex 1–5 nematodes in male birds and 2–8 in females). Ulcerative inflammation and hyperaemia were the most common pathological presentations, especially in areas that had been invaded by parasites. Microscopically, varying degrees of granulomatous inflammatory reactions were seen, in addition to degenerated nematodes which appeared to have deeply penetrated mucosal surfaces and were surrounded by fibrous connective tissues.

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Cormorants dive through the Polar night

Biology Letters ◽

10.1098/rsbl.2005.0356 ◽

2005 ◽

Vol 1 (4) ◽

pp. 469-471 ◽

Cited By ~ 34

Author(s):

David Grémillet ◽

Grégoire Kuntz ◽

Caroline Gilbert ◽

Antony J Woakes ◽

Patrick J Butler ◽

...

Keyword(s):

Visual Cues ◽

Significant Proportion ◽

Dive Depth ◽

Day Length ◽

The Arctic ◽

High Latitudes ◽

Phalacrocorax Carbo ◽

Polar Night ◽

Light Levels ◽

Great Cormorants

Most seabirds are visual hunters and are thus strongly affected by light levels. Dependence on vision should be problematic for species wintering at high latitudes, as they face very low light levels for extended periods during the Polar night. We examined the foraging rhythms of male great cormorants ( Phalacrocorax carbo ) wintering north of the Polar circle in West Greenland, conducting the first year-round recordings of the diving activity in a seabird wintering at high latitudes. Dive depth data revealed that birds dived every day during the Arctic winter and did not adjust their foraging rhythms to varying day length. Therefore, a significant proportion of the dive bouts were conducted in the dark (less than 1 lux) during the Polar night. Our study underlines the stunning adaptability of great cormorants and raises questions about the capacity of diving birds to use non-visual cues to target fish.

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Vision and the foraging technique of Great Cormorants Phalacrocorax carbo: pursuit or close-quarter foraging?

Ibis ◽

10.1111/j.1474-919x.2008.00808.x ◽

2008 ◽

Vol 150 (3) ◽

pp. 485-494 ◽

Cited By ~ 30

Author(s):

GRAHAM R. MARTIN ◽

CRAIG R. WHITE ◽

PATRICK J. BUTLER

Keyword(s):

Phalacrocorax Carbo ◽

Great Cormorants ◽

Close Quarter

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Using stable isotopes to unravel and predict the origins of great cormorants (Phalacrocorax carbo sinensis) overwintering at Kinmen

Rapid Communications in Mass Spectrometry ◽

10.1002/rcm.3487 ◽

2008 ◽

Vol 22 (8) ◽

pp. 1235-1244 ◽

Cited By ~ 19

Author(s):

Yuan-Mou Chang ◽

Kent A. Hatch ◽

Tzung-Su Ding ◽

Dennis L. Eggett ◽

Hsiao-Wei Yuan ◽

...

Keyword(s):

Stable Isotopes ◽

Phalacrocorax Carbo ◽

Phalacrocorax Carbo Sinensis ◽

Great Cormorants

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Infestation of the black cormorants (Phalacrocorax carbo sinensis L. 1758) from the colony on the Selment Wielki, with the nematode Contracaecum rudolphii Hartwich, 1964 (Nematoda, Anisakidae)

Oceanological and Hydrobiological Studies ◽

10.2478/v10009-008-0013-1 ◽

2008 ◽

Vol 37 (4) ◽

Cited By ~ 6

Author(s):

Janina Dziekońska-Rynko ◽

Jerzy Rokicki

Keyword(s):

Seasonal Changes ◽

Phalacrocorax Carbo ◽

Mean Values ◽

Phalacrocorax Carbo Sinensis ◽

Contracaecum Rudolphii ◽

Very High

Infestation of the black cormorants (Seasonal changes in the intensity and prevalence of infestation of the black cormorants from the colony on Lake Selment Wielki were investigated. In 2006, the cormorants were procured in April, August, and October, while in 2007, they were collected in August and September. The prevalence of the infestation was very high and reached 100%. The highest intensity (mean values of 102.46 and 82.17 nematodes/bird in 2006 and 2007, respectively) was revealed in the cormorants shot in August. Intensity of infestation of those birds procured in autumn 2006 was more than twice that found in spring and one-fourth of that found in summer of that year. Similarly, in autumn of 2007, the birds' stomachs contained less than half of the number of nematodes recorded in summer of that year.

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SEASONAL ACCLIMATIZATION IN WILD RATS (RATUS NORVEGICUS)

Canadian Journal of Zoology ◽

10.1139/z63-042 ◽

1963 ◽

Vol 41 (5) ◽

pp. 711-716 ◽

Cited By ~ 17

Author(s):

J. S. Hart ◽

O. Heroux

Keyword(s):

Body Weight ◽

Oxygen Consumption ◽

Seasonal Changes ◽

Size Range ◽

Metabolic Rates ◽

Seasonal Acclimatization ◽

Temperature Range ◽

Wild Rats

Wild rats were collected from dumps at Cornwall, Ontario, and Kingston, Ontario, during summer and winter, and oxygen consumption was measured at various temperatures from 30 °C to −61 °C. Oxygen consumption varied with body weight0.83 over a size range of 100 to 400 g and was slightly but significantly higher for males than for females. The relation of oxygen consumption to temperature was similar in rats collected during summer and winter over the temperature range from 20° to about −10 °C but at lower and higher temperatures winter rats had higher metabolic rates. When tested at −40° the oxygen consumption of winter-caught rats was maintained for at least 50 minutes while that of the summer-caught rats declined progressively. It is concluded that wild rats exhibit a metabolic acclimatization to seasonal changes in their environment.

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