Download or read book Competition for Nests Paternal Care and Female Choice in the Bluntnose Minnow Pimephales Notatus microform written by Pot, Willem and published by National Library of Canada. This book was released on 2015 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Male bluntnose minnows guard eggs that they have fertilized in nests under rocks or other objects on the bottom. Competition for nest sites and its effect on embryo mortality were studied using a method for individual recognition based on the pattern of spots on the males' dorsal surfaces. Over a six-day period, new males replaced the guarding males in about 50% of all the nests in the study pond. When males were removed from nests at the height of the breeding season, new males reoccupied almost all nests within one day, whether the nests contained embryos or not. Males preferred to occupy large nests and nests with more embryos. Males that took over a nest usually guarded at least a portion of the embryos from the previous male. Predation of embryos in guarded nests appeared to be minor, but female bluntnose minnows and other small fish possibly eat embryos during fights between males over nests. Laboratory observations indicated that male size was important in competition for nests, and that males with empty nests were most likely to try to occupy another nest. They also showed that guarding males caused the disappearance of a substantial portion of the embryos in their own nests. It is uncertain whether males removed only dead or diseased embryos or unfertilized eggs, or if they ate healthy embryos as well. Female choice was studied in the field. Nest size and proximity of other nests were not important cues. Females preferred larger males, thus probably increasing the safety of their offspring. In the 1983 breeding season, females preferred males with fewer trematode-caused black spots. In the 1984 breeding season, when the number of black spots per male was significantly lower, no such preference was found. These findings support the theory that genetic variation for parasite resistance is maintained by cycles of coadaptation between hosts and parasites, and that parasite resistance is an important cue in mate choice. There was no detectable influence of the number of trematodes on the wet weight of the males or their ability to compete for nests. The parasites are likely to do more damage to young of the year, however.
Download or read book Muskellunge Management written by Kevin L. Kapuscinski and published by . This book was released on 2017 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Suitability Index Models written by Lynn L. Rogers and published by . This book was released on 1987 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pallid Sturgeon written by and published by . This book was released on 1994 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Survey of Former Shad Streams in Maine written by Clyde C. Taylor and published by . This book was released on 1951 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resource Publication written by and published by . This book was released on 1981 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aquatic Plant Control Research Program written by and published by . This book was released on 1991 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Classification of Wetlands of the United States written by United States. Fish and Wildlife Service. Wetlands Classification Committee and published by . This book was released on 1953 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diseases of Domestic Rabbits written by Edward L. Vail and published by . This book was released on 1943 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atlas of the Spawning and Nursery Areas of Great Lakes Fishes Spawning and nursery areas of Great Lakes fishes a summary by geographic area written by U.S. Fish and Wildlife Service. Office of Biological Services and published by . This book was released on 1982 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Three Types of Fish Rearing Ponds written by Roger E. Burrows and published by . This book was released on 1955 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of the ponds studied, no one type could be considered superior under all conditions of fish-cultural operations. The Foster-Lucas pond, however, was definitely inferior to either the circular or raceway type.
Download or read book Ecology of Daphnia in Bull Shoals Reservoir written by Richard L. Applegate and published by . This book was released on 1969 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Life histories of Daphnia galeata mendotae, D. retrocurva, D. parvula, D. ambigua, and D. schoedleri are compared with year class strength and food of threadfin shad in Bull Shoals Reservoir from 1965 to 1967. Maximum population density of daphnids was in April, May, and June. Populations declined to insignificant densities throughout the rest of the year. Declines coincided with the inclusion of Daphnia in the diets of threadfin shad smaller than 14 mm. Declines in the summer of 1967 coincided with both young shad predation and high Leptodora kindtii density. Population changes associated with declining year class strength of threadfin shad were an increase of the large D. schoedleri and Leptodora kindtii from nondetectable or trace densities to relatively large populations, and increase from nondetectable densities of daphnids in the summer to detectable densities, and a twofold to threefold increase in the summer standing crops of Bosmina longirostris.
Download or read book EPA Publications Bibliography written by United States. Environmental Protection Agency and published by . This book was released on 1996 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wildlife Research Report written by and published by . This book was released on 1972 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Waterfowl populations and breeding conditions written by and published by . This book was released on 1952 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biological Survey of Texas written by Vernon Bailey and published by . This book was released on 1905 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
