Breeding Migration of Ambystoma cingulatum in Florida

1997 ◽  
Vol 31 (1) ◽  
pp. 71 ◽  
Author(s):  
John G. Palis
Keyword(s):  
Ambystoma Cingulatum ◽  
Breeding Migration

Migratory dynamics and characteristics of breeding pink salmon (Oncorhynchus gorbuscha) from the Carp River, eastern Lake Superior

1990 ◽  
Vol 68 (4) ◽  
pp. 684-693 ◽  
Author(s):  
Douglas B. Noltie
Keyword(s):  
Lake Superior ◽  
Pink Salmon ◽  
Life Cycles ◽  
Oncorhynchus Gorbuscha ◽  
Gonad Maturation ◽  
Breeding Ecology ◽  
Pink Salmon Oncorhynchus Gorbuscha ◽  
Light Levels ◽  
Breeding Migration ◽  
Fish Remains

The pink salmon (Oncorhynchus gorbuscha) inhabiting the Great Lakes are unique to their species, the completion of their life cycles occurring entirely in fresh water. This report describes the breeding migration and characteristics of spawners from the Carp River, an eastern Lake Superior tributary 70 km north of Sault Ste. Marie, Ontario. Movement into the stream began at dusk each evening in 1983, seemingly in response to decreasing light levels. Nightly catch numbers varied through the 1983, 1984, and 1985 runs with date, river discharge, wind-generated turbulence, and water temperatures, although the influence of these factors differed with sex and season. Spawners varied in size through the runs each year but not in the same fashion. Spawner size and condition varied yearly in apparent response to prey abundance. Gonad maturation was complete on stream entry more often in males than in females, though this difference was less pronounced further upstream or after time spent in the river. Degree of secondary sexual character development, complete on stream entry in both sexes, differed in even- and odd-year spawners in relation to condition. The recovery rates of spawned-out males and females did not differ. Tagged fish wandered from the Carp River at a rate of at least 7%, many to spawn in adjacent streams. Despite between-year differences in some parameters, much of the breeding ecology of these fish remains comparable to that of anadromous pink salmon.

scholarly journals Timing and pattern of the post‐breeding migration of some species of passerines through Lombardy, Northern Italy

1986 ◽  
Vol 7 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Mia Schubert ◽  
Alessandra Fedrigo ◽  
Renato Massa
Keyword(s):  
Northern Italy ◽  
Breeding Migration

Functional Maturity in Small Male Snow Crabs (Chionoecetes opilio)

1988 ◽  
Vol 45 (12) ◽  
pp. 2106-2109 ◽  
Author(s):  
G. P. Ennis ◽  
R. G. Hooper ◽  
D. M. Taylor
Keyword(s):  
Rapid Development ◽  
Carapace Width ◽  
Reproductive Potential ◽  
Snow Crab ◽  
Small Male ◽  
Chionoecetes Opilio ◽  
In Captivity ◽  
Breeding Migration ◽  
High Level ◽  
Snow Crabs

The mean size of male snow crabs (Chionoecetes opilio) in sexual pairs during the annual spring breeding migration to shallow water in Bonne Bay, Newfoundland, decreased from 118.6 mm carapace width (CW) in 1983 to 100.3 mm in 1987. This decrease is due to an increase in males <95 mm CW participating from 1.5% in 1983 to 32.3% in 1987. This change appears to have resulted from a reduced abundance of commercial size [Formula: see text] males due to a rapid development of an illegal fishery on this previously unfished population and, as a consequence, less competition between males for possession of females. The percentages of spermathecae containing new spermatophores for females paired with males <95 mm CW (67%) and those with males [Formula: see text] (79%) were not significantly different. We assumed that each female with new spermatophores had recently mated with the male with which it was paired. Observations on selected pairs in captivity showed that males <95 mm CW are capable of mating with both primiparous and muitiparous females. Our results indicate that small mature males can replace large males in breeding activity in a snow crab population. We conclude that in the male-only snow crab fishery in Atlantic Canada with a minimum legal size of 95 mm CW, population reproductive potential is maintained at a high level despite high exploitation rates on males [Formula: see text].

scholarly journals Monitoring raptors post-breeding migration on the Elba island, Arcipelago Toscano; years 2005-2006

2012 ◽  
Vol 82 (1/2) ◽  
Author(s):  
Lorenzo Vanni ◽  
Giorgio Paesani
Keyword(s):  
Breeding Migration ◽  
Elba Island

scholarly journals Post-breeding migration of the Swallow, Hirundo rustica, along the coast of Lazio

2012 ◽  
Vol 82 (1/2) ◽  
Author(s):  
Gaspare Guerrieri ◽  
Amalia Castaldi
Keyword(s):  
Hirundo Rustica ◽  
Breeding Migration

Confirmation of little eagle (Hieraaetus morphnoides) migration by satellite telemetry

2018 ◽  
Vol 66 (4) ◽  
pp. 247 ◽  
Author(s):  
Renée Brawata ◽  
Stuart Rae ◽  
Bernd Gruber ◽  
Sam Reid ◽  
David Roberts
Keyword(s):  
Adult Male ◽  
Return Migration ◽  
Satellite Telemetry ◽  
Northern Territory ◽  
Australian Capital Territory ◽  
Satellite Transmitter ◽  
Eastern Australia ◽  
Breeding Migration ◽  
Open Woodland ◽  
The City

The post-breeding migration of an adult male little eagle (Hieraaetus morphnoides) was followed from south-eastern Australia to the Northern Territory using a GPS satellite transmitter. The bird bred in open woodland habitat on the edge of the city of Canberra, Australian Capital Territory (ACT), before it flew more than 3300km in 18 days, to winter in an area of eucalypt savannah in the Northern Territory. It remained there for 59 days, within a range of ~30km2, after which the last signal was transmitted. The bird was subsequently resighted back in its ACT territory at the end of winter, thus completing a return migration. This is the first confirmation of post-breeding migration for the species.

scholarly journals Evolution of moult-migration is directly linked to aridity of the breeding grounds in North American passerines

2020 ◽  
Vol 16 (6) ◽  
pp. 20200155
Author(s):  
Claudie Pageau ◽  
Christopher M. Tonra ◽  
Mateen Shaikh ◽  
Nancy J. Flood ◽  
Matthew W. Reudink
Keyword(s):  
North American ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Autumn Migration ◽  
Western North America ◽  
Migration Distance ◽  
Migration Strategy ◽  
Breeding Grounds ◽  
Breeding Migration ◽  
Moult Migration

To avoid energy allocation conflicts, birds generally separate breeding, migration and moult during the annual cycle. North American passerines typically moult on the breeding grounds prior to autumn migration. However, some have evolved a moult-migration strategy in which they delay moult until stopping over during autumn migration. Rohwer et al . (2005) proposed the ‘push–pull hypothesis' as an explanation for the evolution of this moult strategy, but it has not been empirically tested. Poor conditions on the breeding grounds at the end of the summer would push birds to depart prior to moult, while productive stopover locations would pull them. We tested for a relationship between moult-migration and breeding grounds aridity as measured by the normalized difference vegetation index. Our results strongly support the ‘push' aspect of the push–pull hypothesis and indicate that arid breeding grounds, primarily in western North America, would drive species to evolve stopover moult-migration, although this relationship may depend upon migration distance.

scholarly journals When and where mortality occurs throughout the annual cycle changes with age in a migratory bird: individual vs population implications

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Fabrizio Sergio ◽  
Giacomo Tavecchia ◽  
Alessandro Tanferna ◽  
Julio Blas ◽  
Guillermo Blanco ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Annual Cycle ◽  
Migratory Bird ◽  
Seasonal Effects ◽  
Conservation Strategies ◽  
Gps Tracking ◽  
Milvus Migrans ◽  
Black Kite ◽  
Breeding Migration

AbstractThe annual cycle of most animals is structured into discrete stages, such as breeding, migration and dispersal. While there is growing appreciation of the importance of different stages of an organism’s annual cycle for its fitness and population dynamics, almost nothing is known about if and how such seasonal effects can change through a species lifespan. Here, we take advantage of the opportunity offered by a long-term satellite/GPS-tracking study and a reliable method of remote death-detection to show that certain stages of both the annual and life cycle of a migratory long-lived raptor, the Black kite Milvus migrans, may represent sensitive bottlenecks for survival. In particular, migratory journeys caused bursts of concentrated-mortality throughout life, but the relative importance of stage-specific survival changed with age. On the other hand, the balance between short-stages of high mortality and long-stages of low mortality made population-growth similarly dependent on all portions of the annual cycle. Our results illustrate how the population dynamics of migratory organisms can be inextricably linked to ecological pressures balanced over multiple stages of the annual cycle and thus multiple areas of the globe, suggesting the frequent need for challenging conservation strategies targeting all portions of a species year-round range.

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