803 research outputs found

    Experimental Management of a Group of Small Michigan Lakes

    Full text link
    Eight small pit lakes, located in the Pigeon River State Forest, were considered to be ecologically suited to trout as determined by a physical, chemical, and biological survey of these lakes in 1931 and 1932. Four of the lakes were found to be over‐run with yellow perch, the other four originally contained only forage fish. Trout (chiefly brook trout) were stocked in each of the lakes. They grew and survived well in those lakes which did not contain perch but were relatively unsuccessful in the “perch” lakes. One of these lakes was fertilized with phosphate and later yielded both trout and perch of fair size, the other three were poisoned and later restocked with trout and, in one instance, with Montana grayling.The trout were not easily caught in mid‐summer, and, for this reason, the lakes were opened to fishing during the regular trout fishing season starting about May first.Creel census on some of these lakes for several seasons indicates that the yield varied from 4.3 pounds per acre of trout in one lake to 30 pounds per acre of trout in another lake.These lakes, once valueless for fishing, are now attracting some of the anglers away from the heavily fished, perhaps over‐fished, section of the Pigeon River which flows through the immediate vicinity.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141534/1/tafs0120.pd

    The fishes of ascension Island, central Atlantic Ocean - new records and an annotated checklist

    Get PDF
    A checklist of the fishes of Ascension Island is presented. The species Rhincodon typus, Alopias superciliosus, Isurus oxyrinchus, Carcharhinus obscurus, Galeocerdo cuvier, Sphyrna lewini, Hexanchus griseus, Manta birostris, Gymnothorax vicinus, Hippocampus sp., Epinephelus itajara, Cookeolus japonicus, Apogon pseudomaculatus, Phaeoptyx pigmentaria, Remora albescens, Caranx bartholomaei, Carangoides ruber, Decapterus tabl, Seriola dumerili, Thalassoma sanctaehelenae, Cryptotomus sp., Ruvettus pretiosus, Acanthocybium solandri, Auxis rochei, Auxis thazard, Euthynnus alletteratus, Katsuwonus pelamis, Thunnus alalunga, Thunnus obesus, Xiphias gladius, Istiophorus platypterus, Kajikia albida, Makaira nigricans, Tetrapturus pfluegeri, Hyperoglyphe perciformis, Schedophilus sp., Cantherhines macrocerus, Sphoeroides pachygaster and Diodon eydouxii are recorded for the first time from Ascension Island. We have recognized two previous records as identification errors and indicate 11 other records as doubtful. Including the 40 new records, we now list 173 fish species from Ascension Island, of which 133 might be considered 'coastal fish species'. Eleven of these (8.3%) appear to be endemic to the island and a further 16 species (12%) appear to be shared endemics with St Helena Island.Darwin Initiative [EIDCF012]info:eu-repo/semantics/publishedVersio

    The Pygmy Whitefish, Coregonus Coulteri, in Lake Superior

    Full text link
    Bottom trawling by the U. S. Fish and Wildlife Service motor vessel Cisco in Lake Superior in 1952–1953 revealed a large population of a tiny whitefish, Coregonus (Prosopium) coulteri, which has been reported previously only from northwestern North America. The hiatus in range, from Lake Superior to the Columbia River basin, is the greatest known for a North American freshwater fish. Although minor structural differences characterize the disjunct populations of the pygmy whitefish, these are not deemed worthy of nomenclatorial recognition. Comparisons with related species indicate that the pygmy whitefish is distinctive in the small size, large scales, few vertebrae, few pyloric caeca, and in other characters.The pygmy whitefish is widely distributed in Lake Superior, especially in semi‐protected bays, such as Keweenaw Bay which yielded about 68 percent of the 1,623 specimens caught. The bathymetric range was 10 to 49 fathoms, with maximum abundance at the 25‐ to 39‐fathom interval. Average length of fish increased progressively with water depth, chiefly because the number of yearlings declined from 100 percent at 10–14 fathoms to none at 45–49 fathoms.The average total length of pygmy whitefish caught by trawling was 3.4 inches (range 1.2 to 5.7). Extraordinarily slow growth was revealed by the examination of scales. Two fish from Keweenaw Bay, both nearing the end of their eighth growing season, were only 5.4 inches long. Compared to Keweenaw Bay, growth rate was about the same near Laughing Fish Point, faster in the Apostle Islands (and in Bull and McDonald Lakes, Montana), and slower in Siskiwit Bay, Isle Royale. Females grew more rapidly than males after the second year and had a longer life span.All male pygmy whitefish were mature at the age of 2 years and a total length of 3.6 or more inches. Most females were mature at 3 years and 4.2 inches; all older females were mature. Mean egg production was 362 (range, 93 to 597) per fish and 26 per gram of total weight for fish from 3.4 to 5.9 inches long. Spawning in 1953 occurred sometime in November or December.Crustacea (principally ostracods and amphipods–copepods in the young) occurred in 106 of 112 pygmy whitefish stomachs and made up 77 percent of the total food volume. When available, fish eggs appear to be important in the diet.Other cold‐water fishes–cottids, ninespine sticklebacks, smelt, and four species of coregonines–were the most frequent associates of the pygmy whitefish. Lake trout and trout‐perch were also taken with it at the same stations or in the same trawl hauls. Its closest relative in Lake Superior, the round whitefish, was not an ecological associate.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141996/1/tafs0161.pd

    BIBLIOGRAPHY OF RESEARCH PUBLICATIONS OF THE U.S. BUREAU OF SPORT FISHERIES AND WILDLIFE, 1928-72

    Get PDF
    This bibliography comprises publications in fishery and wildlife research authored or coauthored by research scientists of the Bureau of Sport Fisheries and Wildlife and certain predecessor agencies. Separate lists, arranged alphabetically by author, are given for each of 17 fishery research and 6 wildlife research laboratories, stations, investigations, or centers. Publications coauthored by Bureau scientists from different research units are credited to the facility at which the senior author was stationed at the time of publication. Although the Federal Government has supported research on fish and wildlife since the late 1800\u27s, the relatively few works published in the early years are not directly identifiable with the existing or recent research units whose bibliographies are included here. Consequently the present lists, with three exceptions, are limited to the contributions of facilities that began operation in or after 1939, the year in which the Department of the Interior was given responsibility for fishery and wildlife research. The exceptions are the Great Lakes Fishery Laboratory (established in 1927), the Tunison Laboratory of Fish Nutrition (1932), and the Western Fish Disease Laboratory (1935)

    AN ANALYSIS OF FISHING IN THE TVA IMPOUNDMENTS DURING 1939

    Get PDF
    An inventory of fishing on Norris, a storage reservoir, was begun in 1938. The following year it was extended to Wheeler, a run-of-the-river reservoir, and to the tailwater area below Wilson Dam. This inventory, therefore, covered each of the three general types of fish habitats created by the TVA dams. This discussion is a summary of the 1939 fishing data, together with recommendations for fish management based on the creel census information. The data collected totaled 34,270 usable fishing records, representing a catch of 98,495 fishes

    Disentangling the Taxonomy of the Mahseers (Tor spp.) of Malaysia: An Integrated Approach Using Morphology, Genetics and Historical Records

    Get PDF
    The establishment of appropriate taxonomic designations is essential for the effective management of fishery resources. Despite over a century of explorations and research, the cyprinid genus Tor represents a group of large-bodied freshwater fishes whose taxonomy and systematics remains poorly known. While five species of Tor are currently listed as “endangered” on the IUCN Red List, a further five out of 18 species currently recognized are assessed as “data deficient,” with at least one undescribed species, believed to be on the brink of extinction (i.e., the Humpback Mahseer endemic to the Cauvery River in India). Tor mahseers represent a suitable model for the application of an integrated approach using morphology, genetics, and historical records to resolve species identities, where one or more of these fundamental approaches may have been deficient in the past. Focusing specifically on the taxonomy and nomenclature of the Tor species recorded from Peninsular Malaysia, one of the aims of this review is to define the identity of two nominal species, T. tambra and T. tambroides. Original descriptions of these two nominal species contain little or practically no characters to distinguish them, and partly explains why secondary literature fails to conclusively determine species boundaries. A phylogenetic analysis of mahseer specimens from this region, based on publicly available and newly sequenced mitochondrial COX1 genes, does not support species designation based on previously established morphological features. More importantly, multiple tree-based species delimitation approaches showed that previously sequenced T. tambroides from Peninsular Malaysia and the newly described Tor species from Vietnam could not be delimited from the topotypic Tor tambra. A wider investigation of mahseer taxonomy covering all of Southeast Asia, using such an integrated approach is recommended to resolve the ambiguous taxonomy and is of profound importance for the conservation and management of exploited and farmed populations of these highly valued and iconic fish

    C.C.C. Stream Improvement Work in Michigan

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141739/1/tafs0404.pd

    Unlocking the potential of ancient fish DNA in the genomic era.

    Get PDF
    Fish are the most diverse group of vertebrates, fulfil important ecological functions and are of significant economic interest for aquaculture and wild fisheries. Advances in DNA extraction methods, sequencing technologies and bioinformatic applications have advanced genomic research for nonmodel organisms, allowing the field of fish ancient DNA (aDNA) to move into the genomics era. This move is enabling researchers to investigate a multitude of new questions in evolutionary ecology that could not, until now, be addressed. In many cases, these new fields of research have relevance to evolutionary applications, such as the sustainable management of fisheries resources and the conservation of aquatic animals. Here, we focus on the application of fish aDNA to (a) highlight new research questions, (b) outline methodological advances and current challenges, (c) discuss how our understanding of fish ecology and evolution can benefit from aDNA applications and (d) provide a future perspective on how the field will help answer key questions in conservation and management. We conclude that the power of fish aDNA will be unlocked through the application of continually improving genomic resources and methods to well-chosen taxonomic groups represented by well-dated archaeological samples that can provide temporally and/or spatially extensive data sets
    corecore