scholarly journals Defining Moults in Migratory Birds: A Sequence-based Approach

2021 ◽  
Author(s):  
Peter Pyle
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Migratory Birds ◽  
Autumn Migration ◽  
Evolutionary Approach ◽  
Breeding Period ◽  
P System ◽  
Migratory Species ◽  
Cycle System ◽  
Factors Influencing

Two broad nomenclatures have emerged to describe moult strategies in birds, the "life-cycle" system which describes moults relative to present-day breeding and other life-history events and the Humphrey-Parkes (H-P) system which reflects the evolution of moults along ancestral lineages. Using either system, challenges have arisen defining strategies in migratory species with more than one moult per year. When all or part of two moults occur in non-breeding areas they may fail to be recognized as two moults or have been discriminated temporally, whether feathers are replaced in fall, winter, or spring. But in some cases feather replacement can span the non-breeding period, and this has resulted in an inability to identify inserted moults and to compare moult strategies between species. Furthermore, recent analyses on factors influencing the extent of the postjuvenile or preformative moults have either confined this moult to the summer grounds or presumed that it can be suspended and resumed on winter grounds, which has lead to quite divergent results. Evolutionarily, the timing, extent, and location of moults are very plastic whereas the sequence in which feathers are replaced is comparatively fixed. As, such, I propose taking an evolutionary approach to define moults on the basis of feather-replacement sequences as opposed to timing or location of replacement, including strategies in which moults can overlap temporally. I provide examples illustrating the functionality of a sequence-based definition in three migratory North American passerines that can undergo feather replacement twice in non breeding areas, and I demonstrate how this system can effectively apply to moults in many other passerine and non-passerine species. I recommend that authors studying the evolutionary drivers of moult strategies in migratory birds adopt a sequence-based approach or carefully consider replacement strategies both prior to and following autumn migration.

scholarly journals A STUDY OF THE LIFE HISTORY OF TRICHOBILHARZIA CAMERONI SP. NOV. (FAMILY SCHISTOSOMATIDAE)

1953 ◽  
Vol 31 (4) ◽  
pp. 351-373 ◽  
Author(s):  
Liang-Yu Wu
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Room Temperature ◽  
Migratory Birds ◽  
Local Infection ◽  
Domestic Ducks ◽  
Ottawa River ◽  
Daughter Sporocyst ◽  
Physa Gyrina ◽  
History Of

A cause of swimmer's itch in the lower Ottawa River is Trichobilharzia cameroni sp. nov. Its life cycle has been completed experimentally in laboratory-bred snails and in canaries and ducks, and the various stages are described. The eggs are spindle-shaped. The sporocysts are colorless and tubular. Mother sporocysts become mature in about a week. The younger daughter sporocyst is provided with spines on the anterior end and becomes mature in about three weeks. The development in the snail requires from 28 to 35 days. A few cercariae were found to live for up to 14 days at 50 °C., although their life at 16° to 18 °C. was about four days. Cercariae kept at room temperature for 60 to 72 hr. were found infective. The adults become mature in canaries and pass eggs in about 12 to 14 days. Physa gyrina is the species of snail naturally infected. It was found in one case giving off cercariae for five months after being kept in the laboratory. Domestic ducks were found to become infected until they were at least four months old, with the parasites developing to maturity in due course; no experiments were made with older ducks. Furthermore, miracidia were still recovered from the faeces four months after the duck had been experimentally infected, and it is suggested that migratory birds are the source of the local infection.

THE ECOLOGY AND LIFE HISTORY OF RETUSA OBTUSA (MONTAGU) (GASTROPODA, OPISTHOBRANCHIA)

1967 ◽  
Vol 45 (4) ◽  
pp. 397-405 ◽  
Author(s):  
S. Tyrell Smith
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Life Span ◽  
High Tide ◽  
Breeding Period ◽  
Protandrous Hermaphrodite ◽  
History Of ◽  
Natural Breeding ◽  
One Year ◽  
Short Time

The habitat, diet, life history, and reproductive cycle of Retusa obtusa were investigated over a period of [Formula: see text] years in a population found in the Inner Harbour at Barry, Glamorgan, U.K. A technique was devised for extracting Retusa from the mud of this area. R. obtusa occurs in the topmost 3.5 cm of fine mud covering Barry harbor, which is immersed by the sea for only a short time at each high tide. The principal prey was found to be Hydrobia ulvae.The life cycle was found to be annual, the adults dying in spring, following the natural breeding season. Occasionally, a short extra breeding period occurs in the fall. The life span in no case greatly exceeded one year. Retusa is a protandrous hermaphrodite, and copulates in the fall. The eggs mature through the late fall and the winter, a few at a time, until oviposition occurs in the spring. The average number of eggs produced per individual was 33, deposited in 1–4 egg batches. Development is direct.

Some Aspects of the Life History of Calanus plumchrus in the Strait of Georgia

1973 ◽  
Vol 30 (6) ◽  
pp. 811-815 ◽  
Author(s):  
John Fulton
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Life Cycle ◽  
Breeding Period ◽  
Strait Of Georgia ◽  
History Of

Calanus plumchrus did not feed during the last 7 months of its life cycle and the fecundity of each female was dependent on the size of the animal. Each female produced an average of 535 eggs from 9.5 broods over a breeding period of 85 days. Eggs were released in water deeper than 300 m and were calculated to move towards the surface about 26 m/day. Growth from egg to stage V took about 100 days. Growth rate was calculated to be 10.6%/day.

scholarly journals Protogyny in Autumn Migration: Do Male Birds ”Play Chicken”?

The Auk ◽  
2005 ◽  
Vol 122 (1) ◽  
pp. 71-81 ◽  
Author(s):  
Alexander M. Mills
Keyword(s):  
Migratory Birds ◽  
Indirect Selection ◽  
Male Competition ◽  
Autumn Migration ◽  
Direct Selection ◽  
Differential Migration ◽  
The North ◽  
Parsimonious Explanation ◽  
Ground Conditions ◽  
Wintering Ground

AbstractProtandry, the earlier arrival of males than of females on breeding areas, occurs in many taxa, including many migratory birds. Numerous hypotheses have been generated to explain protandry. Using bird-banding records, I show that protogyny, the earlier migration of females, frequently occurs in the autumn, though it is less universal and less dramatic than spring protandry. In one species, it occurs in both hatch-year and adult birds. When (1) spring and autumn, (2) departures and arrivals, and (3) breeding and wintering ground conditions are considered, hypotheses generated only to explain spring protandry can be more thoroughly evaluated. Using that approach, the most parsimonious explanation of differential migration between the sexes explains earlier male arrival in spring and later male departure in autumn through either (1) indirect selection operating on intrasexual male competition for territories or (2) direct selection operating on intersexual relations requiring males to be present on breeding territories when females are present. In autumn-protogynous species, males may ”play chicken,” balancing the benefits of remaining longer than females and protecting territories for subsequent years against the costs of remaining in the north under deteriorating conditions and delaying the acquisition of a good winter territory.Protogynie et migration automnale: Est-ce que les mâles ”jouent les dégonflés”?

Demographic life history traits of reproductive natterjack toads (Bufo calamita) vary between northern and southern latitudes

2006 ◽  
Vol 27 (3) ◽  
pp. 365-375 ◽  
Author(s):  
Delfi Sanuy ◽  
Christoph Leskovar ◽  
Neus Oromi ◽  
Ulrich Sinsch
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Large Female ◽  
Breeding Period ◽  
Female Size ◽  
Data Set ◽  
Bufo Calamita ◽  
Trade Offs ◽  
Age Variation ◽  
The Cost

AbstractDemographic life history traits were investigated in three Bufo calamita populations in Germany (Rhineland-Palatinate: Urmitz, 50°N; 1998-2000) and Spain (Catalonia: Balaguer, Mas de Melons, 41°N; 2004). We used skeletochronology to estimate the age as number of lines of arrested growth in breeding adults collected during the spring breeding period (all localities) and during the summer breeding period (only Urmitz). A data set including the variables sex, age and size of 185 males and of 87 females was analyzed with respect to seven life history traits (age and size at maturity of the youngest first breeders, age variation in first breeders, longevity, potential reproductive lifespan, median lifespan, age-size relationship). Spring and summer cohorts at the German locality differed with respect to longevity and potential reproductive lifespan by one year in favour of the early breeders. The potential consequences on fitness and stability of cohorts are discussed. Latitudinal variation of life history traits was mainly limited to female natterjacks in which along a south-north gradient longevity and potential reproductive lifespan increased while size decreased. These results and a review of published information on natterjack demography suggest that lifetime number of offspring seem to be optimized by locally different trade-offs: large female size at the cost of longevity in southern populations and increased longevity at the cost of size in northern ones.

scholarly journals Evolutionary Approach for an Optimized Analysis of Product Life Cycle Data

2014 ◽  
Vol 15 ◽  
pp. 359-368 ◽  
Author(s):  
Roland Lachmayer ◽  
Iryna Mozgova ◽  
Bastian Sauthoff ◽  
Philipp Gottwald
Keyword(s):  
Life Cycle ◽  
Product Life Cycle ◽  
Evolutionary Approach ◽  
Product Life

The life-cycle of Echinoparyphium hydromyos sp.nov. (Digenea: Echinostomatidae) from the Australian water-rat

Parasitology ◽  
1967 ◽  
Vol 57 (1) ◽  
pp. 19-30 ◽  
Author(s):  
L. Madeline Angel
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Experimental Work ◽  
Field Work ◽  
Type Material ◽  
South Australian Museum ◽  
The South ◽  
Australian Water ◽  
Australian Museum ◽  
Hydromys Chrysogaster

Echinoparyphium hydromyos sp.nov. with forty-five collar spines is described from the Australian water rat, Hydromys chrysogaster Geoffr.The cercaria occurs naturally in Plananisus isingi (Cotton & Godfrey), and all stages in the life-history have been demonstrated experimentally.Encystation occurs in the kidneys of tadpoles.The adult is most closely related to Echinoparyphium recurvatum (Linstow). It differs from this in its greater number of eggs and in its life-history. E. recurvatum occurs predominantly in birds, and is rarely found naturally in mammals. E. hydromyos has been found only in a mammal.Cercaria echinoparyphii hydromyos is compared with C. clelandae Johnston and Angel; it differs from the latter in the ‘compound’ nature of the excretory granules. The adult of C. clelandae has not been demonstrated in spite of a number of experiments to determine it.Type material has been deposited in the South Australian Museum.I wish to acknowledge the help given by my colleague, Patricia M. Thomas, in field work and in other ways, and by Mr Ian Smith, of this department, in the experimental work on life-history studies.

Life history and pathogenicity of Eimeria adenoeides Moore & Brown, 1951, in the turkey poult

Parasitology ◽  
1958 ◽  
Vol 48 (1-2) ◽  
pp. 70-88 ◽  
Author(s):  
M. J. Clarkson
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Great Britain ◽  
General Pattern ◽  
Blood Picture ◽  
Highly Pathogenic ◽  
Turkey Poult ◽  
Turkey Poults ◽  
Cell Inoculation ◽  
Microscopic Pathology

The life cycle and pathogenicity of a strain of Eimeria isolated in Great Britain from turkey poults by single cell inoculation are described and, using the criteria laid down by Tyzzer, the species is identified as E. adenoeides.The life cycle is of the same general pattern as in other Eimeria species, consisting of two asexual and one sexual generations.The organism is highly pathogenic for young poults, a dose of 200,000 oocysts producing 100 % mortality in 3-week-old birds and smaller doses causing reduced weight gain. Birds 11 weeks old resisted a dose of 3 million oocysts.The gross and microscopic pathology of the infection is described. No changes were found in the blood picture.

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