Harbour Porpoises (Phocoena phocoena): Investigation of Density, Distribution Patterns, Habitat Use and Acoustics in the German North and Baltic Seas

2006 ◽  
pp. 37-64
Author(s):  
Ursula Siebert ◽  
Harald Benke ◽  
Guido Dehnhardt ◽  
Anita Gilles ◽  
Wolf Hanke ◽  
...  
Keyword(s):  
Habitat Use ◽  
Density Distribution ◽  
Distribution Patterns ◽  
Phocoena Phocoena

Changes in Habitat Use and Feeding Chronology of Juvenile Rainbow Trout (Oncorhynchus mykiss) in Fall and the Onset of Winter in Silver Creek, Idaho

1993 ◽  
Vol 50 (10) ◽  
pp. 2119-2128 ◽  
Author(s):  
Michael D. Riehle ◽  
J. S. Griffith
Keyword(s):  
Rainbow Trout ◽  
Habitat Use ◽  
Oncorhynchus Mykiss ◽  
Density Distribution ◽  
Stomach Contents ◽  
Early Morning ◽  
Invertebrate Drift ◽  
Juvenile Rainbow Trout ◽  
Rainbow Trout Oncorhynchus Mykiss

We assessed changes in density, distribution, and microhabitat of age-0 rainbow trout (Oncorhynchus mykiss) in Silver Creek, a partially spring-fed stream, by periodic snorkeling in August 1987 through January 1988. We examined trout stomach contents and invertebrate drift samples in diel collections in August, September, October, and January to test if the period of feeding shifted from daytime to nighttime, concurrent with a transition to day concealment. In late September, fish aggregated briefly during the day and then began to conceal themselves in macrophyte beds, undercut banks, and submerged sedges and grasses along streambanks as temperature dropped below 8 °C in early October. Fish emerged from concealment at night, and numbers of trout visible were greatest 30–60 min after sunset and about 30 min before sunrise. Periods of peak feeding changed from afternoon and evening in August and September, when fish were day active, to mainly at night in October after the initiation of day concealment. Trout did not feed upon abundant chironomids in the daytime drift in October. In January, fish fed at 1–4 °C on mayflies, and stomachs were fullest in the early morning. Observations suggest that Silver Creek trout experienced a metabolic deficit that began in September.

scholarly journals Prespawning Movements and Spawning Distribution of Sockeye Salmon in an Urbanizing Alaskan Lake

2015 ◽  
Vol 6 (2) ◽  
pp. 472-485 ◽  
Author(s):  
James D.M. Ray ◽  
Suresh A. Sethi ◽  
John H. Eiler ◽  
John E. Joyce
Keyword(s):  
Habitat Use ◽  
Sockeye Salmon ◽  
Planning Process ◽  
Current Knowledge ◽  
Fish Habitat ◽  
Black Bear ◽  
Distribution Patterns ◽  
Shoreline Development ◽  
Land Planning ◽  
Salmon Population

Abstract The efficacy of fish habitat conservation in land planning processes in Alaska is often constrained by the extent of current knowledge of fish distributions and habitat use. In response to requests for information from land and salmon resource management stakeholders regarding Auke Lake sockeye salmon (Oncorhynchus nerka) status and life history, we examined the prespawning movements and spawning distribution of adult sockeye salmon to provide ecological information needed for Auke Lake watershed management. We used radiotelemetry to track the movements of 80 fish in the Auke Lake watershed during 2012. The prespawning distribution of the fish was not random, indicating five spatially and temporally distinct high-use staging areas within the lake. The Auke Lake sockeye salmon population was dominated by stream-spawning fish (98.5%), with minimal lakeshore spawning (1.5%) observed in association with a small intermittent tributary of the lake. The prespawning distribution patterns identified in this study corroborate observations from Auke Lake 20 y ago, indicating consistent habitat use patterns by sockeye salmon in the lake. Telemetry data also indicate 12% of sockeye salmon expired in Auke Lake without spawning and that 14% of stream-spawning fish were preyed upon by black bear (Usrus americanus). The prespawning and spawning behavior by Auke Lake sockeye salmon suggest that discrete lake staging areas and stream spawning beds are important candidate habitats for protection during the land planning process for shoreline development surrounding the lake.

scholarly journals The harbour porpoise (Phocoena phocoena) in the North Atlantic: Variability in habitat use, trophic ecology and contaminant exposure

2003 ◽  
Vol 5 ◽  
pp. 223 ◽  
Author(s):  
Arne Bjørge
Keyword(s):  
Habitat Use ◽  
North Atlantic ◽  
Coastal Waters ◽  
Trophic Ecology ◽  
Point Sources ◽  
Phocoena Phocoena ◽  
Cetacean Species ◽  
Contaminant Exposure ◽  
The North ◽  
Management Plans

Harbour porpoises inhabit coastal waters, in habitats that are characterized by high diversity and complexity in terms of their bathymetry, substrate, fish communities and point sources of contaminants. The complexity in these habitats influences both the habitat use and feeding ecology of porpoises. Congregations of porpoises feeding primarily on one species are observed in some areas and seasons, while wide movements and diets composed of several species are observed in other areas. Due to these observations, this paper suggests that caution is needed when extrapolatingknowledge from one area to another with regard to porpoise habitat use, exposure to contaminants, and interactions with fisheries. Management plans should be site specific and based on local knowledge incorporating porpoise population structure, habitat use, and multiple environmental factors in order to ensure appropriate conservation of this abundant but still vulnerable small cetacean species.

scholarly journals Bimodal habitat use in brood parasitic Common Cuckoos (Cuculus canorus) revealed by GPS telemetry

The Auk ◽  
2019 ◽  
Vol 136 (2) ◽  
Author(s):  
Csaba Moskát ◽  
Miklós Bán ◽  
Attila Fülöp ◽  
Judit Bereczki ◽  
Márk E Hauber
Keyword(s):  
Home Range ◽  
Habitat Use ◽  
Distribution Patterns ◽  
Home Ranges ◽  
Cuculus Canorus ◽  
Utilization Distribution ◽  
Minimum Convex Polygon ◽  
Reed Beds ◽  
Male And Female ◽  
Distribution Maps

Abstract Obligate brood parasitic birds have evolved a rare avian strategy for reproduction by laying eggs in the nests of other species. In doing so, their breeding ranges, but not necessarily their foraging habitats, have become intimately related to the nesting territories of their hosts. We studied home range sizes and distribution patterns in Common Cuckoos (Cuculus canorus) on their breeding grounds in central Hungary, where cuckoos parasitize only Great Reed Warblers (Acrocephalus arundinaceus) in channel-side reed-beds at a high frequency (>50%). The geographic coordinates of tagged cuckoos were monitored by high-precision, remotely downloadable non-Platform Terminal Transmitter global positioning system (GPS) loggers, attached to 9 females and 6 males. Our results revealed bimodal use of habitat patches: (1) the home ranges of male and female cuckoos were packed densely along the channels where the hosts breed, and their distribution maps had high overlaps between sexes; (2) ~71% of cuckoos also visited nearby woodland patches, presumably for foraging, where the host species was not present. The size of cuckoo home ranges varied to an unusually great extent: 0.3–185 km2 as calculated by the minimum convex polygon method (85%), or 1–17 km2 when calculated by the more suitable kernel density estimation (KDE) method (Utilization Distribution 85%) for patchy habitats. Male and female cuckoos had similar home range sizes as estimated by the KDE method, consisting of 1–4 areas within the 2 habitat types of channel reed-beds and woodlands. No preference was revealed for night roosting locations between the 2 habitats or sexes. Female cuckoos were more likely to use reed-beds in the afternoons, when females parasitize host nests. Remote downloadable GPS methods offer an effective way of tracking cuckoos across large areas, but the estimation of home range sizes requires caution due to this species’ patchy and disconnected habitat use.

scholarly journals LYSOSOMES IN LYMPHOID TISSUE

1967 ◽  
Vol 32 (2) ◽  
pp. 349-364 ◽  
Author(s):  
William E. Bowers ◽  
Christian de Duve
Keyword(s):  
Density Distribution ◽  
Lymphoid Tissue ◽  
High Capacity ◽  
Distribution Patterns ◽  
Soluble Form ◽  
Lymphoid Tissues ◽  
Triton Wr 1339 ◽  
Isopycnic Centrifugation

The density-distribution patterns of various enzymes and of labeled materials have been determined by isopycnic centrifugation in a sucrose—0.2 M KCl gradient on homogenates of lymphoid tissues from rats injected with Triton WR-1339, 14C-labeled dextran, 51Cr-labeled erythrocytes, and cortisol. The results confirm and extend the conclusion, derived from previous investigations on normal animals, that the lysosomes of lymphoid tissues form two and possibly three, distinct populations. The evidence indicates that the L19 population belongs to macrophages and the L15 group to lymphocytes. The L30 population appears to be associated with a special type of phagocyte with a high capacity for dextran storage. All three populations seem to contribute to the activities found in soluble form in homogenates of normal lymphoid tissues.

scholarly journals Prognostic significance of lymphocyte density distribution profiles in adult non-Hodgkin lymphomas

Blood ◽  
1982 ◽  
Vol 60 (6) ◽  
pp. 1397-1401 ◽  
Author(s):  
C Huber ◽  
D Lutz ◽  
D Niederwieser ◽  
G Weiser ◽  
O Dietze ◽  
...  
Keyword(s):  
Density Distribution ◽  
Prognostic Significance ◽  
Distribution Patterns ◽  
Lymphoma Cells ◽  
Biopsy Material ◽  
Spontaneous Proliferation ◽  
Advanced Stages ◽  
Individual Capacity ◽  
The Individual ◽  
Observation Period

Biopsy material from 24 adults with advanced stages of non-Hodgkin lymphomas (NHL) were examined for the distribution profiles of infiltrating cells following centrifugation to equilibrium on linear density gradients. Seven of these biopsies were predominantly composed of cells with high buoyant densities and 9 further biopsies predominantly of cells with intermediate buoyant densities. Both patterns were associated with favorable histologic features and with low proliferation of lymphoma cells. Intensive polychemotherapy was rarely required to achieve long-lasting disease control; in both groups, only 28% of patients died within a minimal observation period of 40 mo. In 8 biopsies, a predominance of light lymphoma cells was observed. This pattern was frequently associated with unfavorable histology and with high spontaneous tumor cell proliferation. Despite intensive polychemotherapy, rapid disease progression occurred in all cases, leading to death in 75% of the patients within a minimal observation period of 40 mo. Surface marker studies excluded the hypothesis that only the variable proportions of normal lymphocytes contaminating the lymphoma suspensions were responsible for the differences in the density distribution patterns described above; they rather suggested that these patterns reflect the individual capacity of a lymphoma to differentiate into dense tumor clones with low spontaneous proliferation.

Stomatal density distribution patterns in leaves of the Jatobá (Hymenaea courbaril L.)

Trees ◽  
2011 ◽  
Vol 26 (2) ◽  
pp. 571-579 ◽  
Author(s):  
Giordane Augusto Martins ◽  
Angela Maria Soares ◽  
João Paulo Rodrigues Alves Delfino Barbosa ◽  
José Marcio de Mello ◽  
Evaristo Mauro de Castro ◽  
...  
Keyword(s):  
Density Distribution ◽  
Stomatal Density ◽  
Distribution Patterns ◽  
Hymenaea Courbaril

Effects of freshwater limitation on distribution patterns and habitat use of the West Indian manatee, Trichechus manatus , in the northern Brazilian coast

2020 ◽  
Vol 30 (8) ◽  
pp. 1665-1673
Author(s):  
Iana Tavares Favero ◽  
Gabriel Eduardo Favero ◽  
Katherine Fiedler Choi‐Lima ◽  
Heleno Francisco Santos ◽  
João Pedro Souza‐Alves ◽  
...  
Keyword(s):  
Habitat Use ◽  
West Indian ◽  
Distribution Patterns ◽  
Brazilian Coast ◽  
The West ◽  
Trichechus Manatus ◽  
West Indian Manatee

scholarly journals Fine-scale habitat selection of Chilean dolphins (Cephalorhynchus eutropia): interactions with aquaculture activities in southern Chiloé Island, Chile

2007 ◽  
Vol 87 (1) ◽  
pp. 119-128 ◽  
Author(s):  
Sandra Ribeiro ◽  
Francisco A. Viddi ◽  
José Luís Cordeiro ◽  
Thales R.O. Freitas
Keyword(s):  
Habitat Selection ◽  
Habitat Use ◽  
Environmental Parameters ◽  
Distribution Patterns ◽  
Fine Scale ◽  
Entire Study ◽  
Use Patterns ◽  
Behavioural Determinants ◽  
Entire Study Area ◽  
Selection Of

Fine-scale habitat selection of Chilean dolphins was studied between January and April 2002 through shore-based theodolite tracking in order to investigate the environmental and behavioural determinants of habitat use, and to evaluate the interactions between this species and aquaculture activities in Yaldad Bay, southern Chile. During 293.5 h of effort, movement and habitat selection patterns of dolphins exhibited a significantly concentrated use of only 21% of the entire study area. Correspondence analysis showed that shallow waters (5–10 m), proximity to coast and rivers were the most significant environmental parameters determining fine-scale dolphin distribution patterns, with foraging the most frequently observed activity. Aquaculture activities in the area were observed to affect dolphin habitat use patterns by restricting space available for biologically important dolphin behaviours.

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