scholarly journals Frogs with denser group-spawning mature later and live longer

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yun Lin Cai ◽  
Chun Lan Mai ◽  
Wen Bo Liao
Keyword(s):  
Group Size ◽  
Mortality Rates ◽  
Age At First Reproduction ◽  
Extrinsic Mortality ◽  
Spawning Site ◽  
Site Density ◽  
Site Group ◽  
Group Spawning ◽  
Predator Behaviour ◽  
Spawning Sites

Abstract The understanding of the intrinsic and extrinsic causes of longevity variation has deservedly received much attention in evolutionary ecologist. Here we tested the association between longevity and spawning-site groups across 38 species of Chinese anurans. As indicators of group-spawning we used spawning-site group size and spawning-site density, which we measured at 152 spawning sites in the field. We found that both spawning-site density and group size were positively associated with longevity. Male group-spawning (e.g., male spawning-site density and male spawning-site group size) was also positively correlated with longevity. A phylogenetic path analysis further revealed that longevity seems directly associated with spawning-site density and group size, and that the association in part depend on the ‘groups-spawning-age at first reproduction’ association. Our findings suggest that the increased group-spawning are likely to benefit in declining extrinsic mortality rates and living longer through improving total anti-predator behaviour under predation pressure.

An Electrophysiological Basis for Olfactory Discrimination in Homing Salmon: A Review

1970 ◽  
Vol 27 (3) ◽  
pp. 565-586 ◽  
Author(s):  
Toshiaki J. Hara
Keyword(s):  
Pacific Salmon ◽  
Electrical Response ◽  
High Amplitude ◽  
Polluted Water ◽  
Sensitive Period ◽  
Young Fish ◽  
Spawning Site ◽  
Short Period ◽  
Sign Stimulus ◽  
Spawning Sites

Past and current researches relating to olfactory acuity and discrimination in fishes, with special reference to homing salmon, are reviewed.When the nasal sac of spawning Pacific salmon is stimulated with water from the spawning site a high amplitude electroencephalographic response of characteristic pattern is recorded from the olfactory bulb. This electrical response is specific in the sense that it cannot be evoked by water from spawning sites of other groups of breeding salmon. Further, the salmon respond clearly to water taken from places along their migratory routes below the spawning sites. These findings suggest that olfaction is an important factor in guidance during the final phases of homeward migration of salmon. It is also possible that salmon retrace sequentially a trail of stimuli that is the reverse of that imprinted in the young fish on their seaward migration.Although the available data do not delineate the sensitive period, or the duration of the imprinting process, there is accumulating evidence that only a short period is necessary for imprinting, which may occur when the smolts are in their freshwater life.Recent study on the effect of antimetabolites (puromycin, actinomycin D, or cycloheximide) on olfactory bulbar discrimination in homing salmon suggests that long-term olfactory memory in these fish depends upon continued metabolism of RNA and continued protein synthesis. The possibility that the imprinting process in young fish may be affected by polluted water, which has recently become a serious problem in fisheries, is discussed. The need for electrophysiological as well as biochemical studies at a macromolecular level of the imprinting process is emphasized.Finally, the hypothesis is discussed that a home stream odour may act most effectively as a simple "sign stimulus," which, through the release of a positive rheotropic response, induces the fish to move upstream toward home. This is largely based on the recent experimental observations of the orientation mechanism in several species of teleost fishes.

Groundwater and the selection of spawning sites by brook trout (Salvelinus fontinalis)

1995 ◽  
Vol 52 (8) ◽  
pp. 1733-1740 ◽  
Author(s):  
R. Allen Curry ◽  
David L. G. Noakes
Keyword(s):  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Limited Area ◽  
Specific Mechanism ◽  
Spawning Site ◽  
Central Pennsylvania ◽  
Spawning Areas ◽  
The Impact ◽  
Selection Of ◽  
Spawning Sites

Spawning areas selected by brook trout (Salvelinus fontinalis) displayed variable relationships to discharging groundwater across geologic regions. In Canadian Shield waters, spawning was associated with areas of distinct, discharging groundwater. The specific mechanism of selection could not be determined. Groundwater did not appear to influence the selection of individual redd sites within these discharge areas. Competition among females for the opportunity to spawn in a limited area defined by the discharging groundwater appeared to control the selection of redd sites. In southwestern Ontario streams, discharging groundwater was prominent throughout areas of spawning both at redds and at adjacent, nonspawning substrates (≤7 m). Consequently, relationships between groundwater and spawning site selection were ambiguous. On the unglaciated plateau of central Pennsylvania, no groundwater was observed in redds or nonspawning substrates in streams. Brook trout management programmes must consider these groundwater relationships and therefore the impact of land use on groundwater quality and quantity.

scholarly journals Is group size related to longevity in mammals?

2010 ◽  
Vol 6 (6) ◽  
pp. 736-739 ◽  
Author(s):  
Jason M. Kamilar ◽  
Richard G. Bribiescas ◽  
Brenda J. Bradley
Keyword(s):  
Group Size ◽  
Life History Theory ◽  
Large Species ◽  
Mammal Species ◽  
Significant Group ◽  
Maximum Longevity ◽  
Extrinsic Mortality ◽  
Risk Of Mortality ◽  
Risk Of Predation ◽  
Extrinsic Risk

Life-history theory predicts that reduced extrinsic risk of mortality should increase species longevity over evolutionary time. Increasing group size should reduce an individual's risk of predation, and consequently reduce its extrinsic risk of mortality. Therefore, we should expect a relationship between group size and maximum longevity across species, while controlling for well-known correlates of longevity. We tested this hypothesis using a dataset of 253 mammal species and phylogenetic comparative methods. We found that group size was a poor predictor of maximum longevity across all mammals, as well as within primates and rodents. We found a weak but significant group-size effect on artiodactyl longevity, but in a negative direction. Body mass was consistently the best predictor of maximum longevity, which may be owing to lower predation risk and/or lower basal metabolic rates for large species. Artiodactyls living in large groups may exhibit higher rates of extrinsic mortality because of being more conspicuous to predators in open habitats, resulting in shorter lifespans.

scholarly journals An investigation of the spawning behaviour of the chokka squid Loligo reynaudii and the potential effects of temperature using acoustic telemetry

2009 ◽  
Vol 67 (2) ◽  
pp. 231-243 ◽  
Author(s):  
Nicola J. Downey ◽  
Michael J. Roberts ◽  
Dan Baird
Keyword(s):  
Acoustic Telemetry ◽  
Environmental Variability ◽  
Spawning Site ◽  
Spawning Aggregations ◽  
Spawning Behaviour ◽  
Effects Of Temperature ◽  
Continuous Presence ◽  
Receiver Arrays ◽  
Spawning Sites

Abstract Downey, N. J., Roberts, M. J., and Baird, D. 2010. An investigation of the spawning behaviour of the chokka squid Loligo reynaudii and the potential effects of temperature using acoustic telemetry. – ICES Journal of Marine Science, 67: 231–243. Spawning aggregations of chokka squid are influenced by environmental conditions. Acoustic telemetry was used to monitor the behaviour of spawning squid in relation to environmental variability. During the November squid-fishery closed seasons of 2003–2006, hexagonal VR2 receiver arrays were moored on and around active spawning aggregations in Kromme Bay, South Africa. In all, 45 squid were tagged (V9P-6L-S256 transmitters) and released within these arrays. Three presence–absence behaviours were identified: (i) arrival on the spawning site at dawn and departure after dusk, (ii) continuous presence for a number of days, and (iii) presence interrupted by frequent but short periods of absence. Movement between spawning sites was both diurnal and nocturnal. Squid presence at the monitored sites increased after dawn and decreased towards and after dusk. Occasionally, a core aggregation of squid remained on the spawning sites at night. Temperature data at the sites indicated occasional upwelling, and although the role of temperature in the spawning process is not well understood, data suggest that it is linked to the continuation and or interruption of spawning after an aggregation has formed. The initial formation of spawning aggregations appears to be triggered by upwelling events.

Movements of adult coho salmon (Oncorhynchus kisutch) during colonization of newly accessible habitat

2007 ◽  
Vol 64 (8) ◽  
pp. 1143-1154 ◽  
Author(s):  
Joseph H Anderson ◽  
Thomas P Quinn
Keyword(s):  
Coho Salmon ◽  
Pacific Salmon ◽  
Oncorhynchus Kisutch ◽  
Conservation Strategy ◽  
Breeding Behavior ◽  
Spawning Site ◽  
Radio Transmitters ◽  
Accessible Habitat ◽  
Initial Process ◽  
Spawning Sites

Pacific salmon (Oncorhynchus spp.) have repeatedly exploited new habitat following glacial recession and some artificial introductions, yet the initial process of colonization is poorly understood. Landsburg Diversion Dam on the Cedar River, Washington, excluded salmon from 33 km of habitat for over a century until it was modified to allow passage in 2003. Adult coho salmon (Oncorhynchus kisutch) were sampled as they entered the newly accessible habitat in the first 3 years and a subset received radio transmitters to assess spawning site selection and movement. Annual counts of coho colonists increased over time, and in 2 of 3 years, daily dam passage was positively correlated with river discharge. Contrary to our prediction that coho would spawn in tributaries, all identified spawning sites were in the mainstem Cedar River, though 38% of radio-tagged salmon entered a tributary at least temporarily. Females moved little within the new habitat (average = 5.8 km), whereas males moved extensively (average = 34.8 km), especially when females were scarce. The immediate use of the new habitat by colonists and their widespread movements suggest that exploration is an innate component of salmon breeding behavior, and restoring access to lost habitat merits prioritization as a conservation strategy.

scholarly journals Discovery of an Undocumented Lake Sturgeon Spawning Site in the Headwaters of the Niagara River

2018 ◽  
Vol 9 (1) ◽  
pp. 266-273 ◽  
Author(s):  
Rachel D. Neuenhoff ◽  
Jonah L. Withers ◽  
Lori A. Davis ◽  
Nicholas D. Markley ◽  
Stephanie Dowell ◽  
...  
Keyword(s):  
Life History ◽  
Early Life ◽  
Lake Erie ◽  
Stock Assessment ◽  
Early Life History ◽  
Lake Sturgeon ◽  
Western Basin ◽  
Niagara River ◽  
Spawning Site ◽  
Spawning Sites

Abstract Information about spawning fish is important to stock-assessment data needs (i.e., recruitment and fecundity) and management (i.e., habitat connectivity and protection). In Lake Erie, information about Lake Sturgeon Acipenser fulvescens early-life history is available for the Detroit River and Lake St. Clair system in the western basin, but fisheries biologists know comparatively little about Lake Sturgeon in the eastern basin. Although researchers have summarized historical spawning areas, no known natural Lake Sturgeon spawning site is described in Lake Erie proper. Researchers documented a remnant population of reproductively mature Lake Sturgeon near the headwaters of the Niagara River in eastern Lake Erie in 2011. Researchers hypothesized that a spawning site was likely in the immediate vicinity of the Niagara River headwaters near Buffalo Harbor, New York; however, its exact location was unknown. We attempted to locate spawning sites near the confluence of the Niagara River using egg traps at three potential spawning sites. We identified Lake Sturgeon eggs at one of these sites using morphological and genetic techniques. Lake Sturgeon eggs collected on one sampling trip began to emerge when placed in preservative, confirming that eggs deposited at this site are fertilized and viable, and that the area supports viable embryos. This discovery fills data gaps in the early-life history for this population, which has domestic and international management implications with respect to proposed recovery targets, stock assessment models, habitat remediation efforts, and status determinations of a protected species in a geographic region designated as an Area of Concern by the International Joint Commission.

scholarly journals Spatial shifts in spawning habitats of Arcto-Norwegian cod related to multidecadal climate oscillations and climate change

2008 ◽  
Vol 65 (6) ◽  
pp. 953-962 ◽  
Author(s):  
Svein Sundby ◽  
Odd Nakken
Keyword(s):  
Climate Change ◽  
Time Scale ◽  
Climate Variations ◽  
Interannual Time Scale ◽  
Climate Oscillations ◽  
Spawning Site ◽  
Spawning Areas ◽  
Response To Temperature ◽  
Spawning Sites ◽  
Spawning Habitats

Abstract Sundby, S., and Nakken, O. 2008. Spatial shifts in spawning habitats of Arcto-Norwegian cod related to multidecadal climate oscillations and climate change. – ICES Journal of Marine Science, 65: 953–962. Arcto-Norwegian cod tend to produce strong year classes in warm years and poor year classes in cold years. This work shows that spawning intensity at various spawning sites along 1500 km of Norwegian coast is also influenced by climate variations. However, while the recruitment response to temperature is immediate and on an interannual time-scale, the response to changes in spawning site is slower, on a multidecadal time-scale. There have been two cold and two warm periods during the 20th century, cold from 1900 to 1920, warm from 1930 to 1950, cold from 1960 to 1970, and warm since the mid-1980s. A time-series for 1900–1976 on cod roe indices along the coast shows that the southernmost spawning areas are more important during cold periods, and the northernmost ones in warm periods, and coincide with high population fecundity. After 1976, qualitative observations show that there have been poor spawning fisheries in the southernmost spawning areas during the present warm period. From 2003, spawning has been observed along the coast of East Finnmark where it did not transpire during the previous 40 years.

scholarly journals A heuristic model of socially learned migration behaviour exhibits distinctive spatial and reproductive dynamics

2018 ◽  
Vol 76 (2) ◽  
pp. 598-608 ◽  
Author(s):  
Alec D MacCall ◽  
Tessa B Francis ◽  
André E Punt ◽  
Margaret C Siple ◽  
Derek R Armitage ◽  
...  
Keyword(s):  
Local Density ◽  
Total Mortality ◽  
Structured Populations ◽  
Older Individuals ◽  
Spawning Site ◽  
Spatially Structured Populations ◽  
Migration Behaviour ◽  
Age Structured ◽  
Proportional Decrease ◽  
Spawning Sites

Abstract We explore a “Go With the Older Fish” (GWOF) mechanism of learned migration behaviour for exploited fish populations, where recruits learn a viable migration path by randomly joining a school of older fish. We develop a non-age-structured biomass model of spatially independent spawning sites with local density dependence, based on Pacific herring (Clupea pallasii). We compare a diffusion (DIFF) strategy, where recruits adopt spawning sites near their natal site without regard to older fish, with GWOF, where recruits adopt the same spawning sites, but in proportion to the abundance of adults using those sites. In both models, older individuals return to their previous spawning site. The GWOF model leads to higher spatial variance in biomass. As total mortality increases, the DIFF strategy results in an approximately proportional decrease in biomass among spawning sites, whereas the GWOF strategy results in abandonment of less productive sites and maintenance of high biomass at more productive sites. A DIFF strategy leads to dynamics comparable to non-spatially structured populations. While the aggregate response of the GWOF strategy is distorted, non-stationary and slow to equilibrate, with a production curve that is distinctly flattened and relatively unproductive. These results indicate that fishing will disproportionately affect populations with GWOF behaviour.

Genetic Population Structure of Atlantic Halibut, Hippoglossus hippoglossus

1988 ◽  
Vol 45 (1) ◽  
pp. 2-7 ◽  
Author(s):  
Svein Erik Fevolden ◽  
Tore Haug
Keyword(s):  
Population Structure ◽  
Genetic Screening ◽  
Atlantic Halibut ◽  
Genetic Population ◽  
Hippoglossus Hippoglossus ◽  
Spawning Site ◽  
Breeding Populations ◽  
Species Population ◽  
Biochemical Genetic ◽  
Spawning Sites

Atlantic halibut, Hippoglossus hippoglossus, have been shown to home to the same spawning site in successive years, suggesting that distinct breeding populations could exist. The species' population structure has, therefore, been studied using biochemical genetic methods to reveal possible genetic differences among fish from different spawning sites. Genetic screening of 43 loci in Faroese halibut revealed only four polymorphic loci, including one highly polymorphic fumarase locus not previously detected in halibut. Comparing these four loci among stocks from the Faroes, the Norwegian coast and Greenland gave evidence of general genetic homogeneity over the sampling range. This lack of genetic differentiation is not taken as proof, but as strong evidence of substantial gene flow between geographical areas.

Sign in / Sign up

Export Citation Format

Share Document