Reproductive success is driven by local site fidelity despite stronger specialisation by individuals for large‐scale habitat preference

Abstract Knowledge of movement ecology, habitat use, and spatiotemporal distribution is critical to inform sustainable fisheries management and conservation. Atlantic halibut in the Gulf of St. Lawrence (GSL) is of great economic value, although little is known about its spatiotemporal distribution, seasonal migrations, and spawning areas. To investigate these aspects, 114 pop-up satellite archival tags (PSATs) were deployed on halibut from 2013 up to 2018 throughout the GSL. A total of 62 physically recovered PSATs provided complete archived datasets with high temporal resolution. PSAT detachment locations revealed specific summer site fidelity. In contrast, the reconstruction of movement tracks with a geolocation model revealed that all fish converged to the Gulf’s deep channels to overwinter and spawn. This suggests strong mixing during the spawning period and thus one reproductive population within the GSL. These findings illustrate the utility of large-scale PSAT tagging combined with dedicated PSAT-recovery surveys to reveal critical stock-scale information on movements and spawning locations. This information addresses important gaps in the movement ecology of this halibut stock, revealing that reported summer site fidelity, based on years of conventional tagging, also conceals important winter mixing that is only apparent through analyses of movement on the time scale of annual cycles.

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Monitoring the effect of habitat loss on life-cycle aspects of the Masked Owl Tyto novaehollandiae in a semi-urban landscape

Australian Zoologist ◽

10.7882/az.2019.005 ◽

2020 ◽

Vol 40 (4) ◽

pp. 565-574

Author(s):

Chris N. Thomson

Keyword(s):

Site Fidelity ◽

Large Scale ◽

Urban Landscape ◽

Negative Impact ◽

Urban Expansion ◽

Short Term ◽

Breeding Activity ◽

Breeding Territory ◽

Term Monitoring

Long-term monitoring of the Masked Owl Tyto novaehollandiae in a semi-urban landscape before, during and after large-scale habitat removal identified a positive response in breeding activity in the short-term and a change in prey selectivity. Over the longer term, the loss in habitat had a negative impact on site fidelity. A pair of Masked Owls exhibited high fidelity to a particular breeding territory before and during the removal of large areas of habitat within this territory. Breeding success occurred over two consecutive seasons during the removal of known habitat and other disturbance events at which time the pair and their offspring were observed to exploit disturbed habitat and newly created forest edges in search of prey. Breeding activity was supported by an increased dietary focus on introduced rodents and other mammals displaced during habitat clearing. Fidelity to the breeding territory became more irregular post-disturbance and after two years the territory appeared to be abandoned. This response may suggest that the cumulative loss of habitat for established pairs as a result of urban expansion is likely to adversely affect reproductive success and site fidelity in the longer term.

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Eastern Baltic cod recruitment revisited—dynamics and impacting factors

ICES Journal of Marine Science ◽

10.1093/icesjms/fsw172 ◽

2016 ◽

Vol 74 (1) ◽

pp. 3-19 ◽

Cited By ~ 26

Author(s):

Friedrich W. Köster ◽

Bastian Huwer ◽

Hans-Harald Hinrichsen ◽

Viola Neumann ◽

Andrei Makarchouk ◽

...

Keyword(s):

Reproductive Success ◽

Large Scale ◽

Prey Availability ◽

Stock Assessment ◽

Future Research ◽

First Feeding ◽

Spawning Areas ◽

The Baltic ◽

Eastern Baltic ◽

Baltic Cod

The Eastern Baltic cod abundance started rapidly to increase in the mid-2000s as evidenced by analytical stock assessments, due to increased recruitment and declining fishing mortality. Since 2014, the analytical stock assessment is not available, leaving the present stock status unclear and casting doubts about the magnitude of the recent increase in recruitment. Earlier studies identified main factors impacting on cod reproductive success to be related to the loss of two out of three spawning areas in the 1980s caused by lack of major Baltic inflows with a concurrent reduction in salinity and oxygen. Other important factors include prey availability for first-feeding larvae, egg predation by sprat and herring and cannibalism on juveniles, all in one way or the other related to the prevailing hydrographic conditions. These factors cannot explain increased reproductive success in the last decade, as the period was characterized by an absence of large-scale Baltic inflows since 2003 and persistent anoxic conditions in the bottom water of the deep Baltic basins. This questions the perception of the increased recruitment in later years and challenges our present understanding of cod recruitment dynamics in the Baltic Sea. In this contribution, we review evidence from the recent literature supplemented by information from latest research cruises to elucidate whether cod reproductive success indeed has increased during the last decade, and we suggest the key processes responsible for the recent dynamics in cod recruitment and outline directions for future research.

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Theoretically possible spatial accuracy of geomagnetic maps used by migrating animals

Journal of The Royal Society Interface ◽

10.1098/rsif.2016.1002 ◽

2017 ◽

Vol 14 (128) ◽

pp. 20161002 ◽

Cited By ~ 6

Author(s):

Andrei V. Komolkin ◽

Pavel Kupriyanov ◽

Andrei Chudin ◽

Julia Bojarinova ◽

Kirill Kavokin ◽

...

Keyword(s):

Field Intensity ◽

Geomagnetic Field ◽

Site Fidelity ◽

Large Scale ◽

Migratory Birds ◽

Time Of Day ◽

Northern Europe ◽

Spatial Accuracy ◽

Total Field ◽

Migrating Birds

Many migrating animals, belonging to different taxa, annually move across the globe and cover hundreds and thousands of kilometres. Many of them are able to show site fidelity, i.e. to return to relatively small migratory targets, from distant areas located beyond the possible range of direct sensory perception. One widely debated possibility of how they do it is the use of a magnetic map, based on the dependence of parameters of the geomagnetic field (total field intensity and inclination) on geographical coordinates. We analysed temporal fluctuations of the geomagnetic field intensity as recorded by three geomagnetic observatories located in Europe within the route of many avian migrants, to study the highest theoretically possible spatial resolution of the putative map. If migratory birds measure total field intensity perfectly and take the time of day into account, in northern Europe 81% of them may return to a strip of land of 43 km in width along one of coordinates, whereas in more southern areas such a strip may be narrower than 10 km. However, if measurements are performed with an error of 0.1%, the strip width is increased by approximately 40 km, so that in spring migrating birds are able to return to within 90 km of their intended goal. In this case, migrating birds would probably need another navigation system, e.g. an olfactory map, intermediate between the large-scale geomagnetic map and the local landscape cues, to locate their goal to within several kilometres.

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Regimes and stock-recruitment relationships in Japanese sardine (Sardinops melanostictus), 1951-1995

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f98-135 ◽

1998 ◽

Vol 55 (11) ◽

pp. 2455-2463 ◽

Cited By ~ 41

Author(s):

Tokio Wada ◽

Larry D Jacobson

Keyword(s):

Reproductive Success ◽

Large Scale ◽

Environmental Changes ◽

Environmental Variability ◽

Population Analysis ◽

Search Time ◽

Data Sets ◽

Japanese Sardine ◽

Density Dependent ◽

Peak Abundance

We used reproductive success, rather than abundance or catch, to identify regimes because reproductive success responds faster to environmental changes. Peak abundance of Japanese sardine during 1951-1995 was about 1000 times higher than minimum abundance. A regime shift occurred in the early 1970s when carrying capacity (measured using spawner-recruit models) increased by about 75 times. We hypothesize that this was due to large-scale changes in the Kuroshio and Oyashio Current systems. Long-term environmental variation (regimes), interannual variability in recruitment success, and density-dependent recruitment and growth rates affected dynamics of Japanese sardine. We hypothesize that density-dependent effects on recruitment of Sardinops spp. are common but usually obscured in short data sets by environmental variability and measurement error. Virtual population analysis and forward-simulation modeling approaches gave similar biomass and recruitment estimates. The relationship between sardine biomass and catch per unit search time was nonlinear. Mass-at-age and biomass were correlated, and it may be possible to use mass-at-age as an abundance index. Current abundance is low, and we believe that the environment has shifted to a regime that is unfavorable for Japanese sardine.

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Interannual site fidelity of Pacific halibut: potential utility of protected areas for management of a migratory demersal fish

ICES Journal of Marine Science ◽

10.1093/icesjms/fsx040 ◽

2017 ◽

Vol 74 (8) ◽

pp. 2120-2134 ◽

Cited By ~ 8

Author(s):

Julie K. Nielsen ◽

Andrew C. Seitz

Keyword(s):

Protected Areas ◽

Site Fidelity ◽

Large Scale ◽

Marine Protected Area ◽

Spatial Scales ◽

Movement Patterns ◽

Demersal Fish ◽

Glacier Bay ◽

Migration Timing ◽

Pacific Halibut

Abstract Pacific halibut is a large-bodied demersal fish species known to undertake large-scale winter spawning migrations. We characterized annual movement patterns of Pacific halibut relative to a Marine Protected Area (MPA) in Glacier Bay National Park, Alaska using electronic tags. In the summer of 2013, we deployed 25 Pop-up Satellite Archival Tags (PSATs) on halibut to determine seasonal movement patterns, where residency within the MPA was inferred by comparing PSAT depth and temperature records to stationary archival tag data and oceanographic survey data. To characterize within-summer movement patterns, 15 halibut tagged with PSATs were double-tagged with acoustic transmitters and actively tracked during the summers of 2013 and 2014. Home range behaviour and interannual site fidelity at spatial scales <5 km were observed for the majority of tagged fish. A small proportion (6/21 fish with PSAT data) departed the MPA on winter migrations during December 2013. A majority (4/6) of migratory fish returned to the MPA after an average of 57 d (s.d. 22 d) spent outside of the MPA. Migration timing generally coincided with existing winter commercial fishery closures. The annual movement patterns of tagged halibut relative to MPA boundaries and winter commercial fisheries closures suggest that the Glacier Bay MPA could serve as a year-round refuge from commercial harvest for both residential and migratory halibut. If halibut behaviour is similar in other areas, protected areas may provide some utility for management despite the migratory nature of halibut.

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Invasion of an exotic forb impacts reproductive success and site fidelity of a migratory songbird

Oecologia ◽

10.1007/s00442-006-0438-8 ◽

2006 ◽

Vol 149 (2) ◽

pp. 340-351 ◽

Cited By ~ 55

Author(s):

Yvette Katina Ortega ◽

Kevin Scot McKelvey ◽

Diana Lee Six

Keyword(s):

Reproductive Success ◽

Site Fidelity ◽

Migratory Songbird

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The terrestrial breeding biology of the ranid rock frog Nannophrys ceylonensis

Behaviour ◽

10.1163/1568539042265653 ◽

2004 ◽

Vol 141 (7) ◽

pp. 899-913 ◽

Cited By ~ 2

Author(s):

◽

Keyword(s):

Reproductive Success ◽

Parental Care ◽

Site Fidelity ◽

Nest Site ◽

Hatching Success ◽

Paternal Care ◽

Adult Males ◽

Nest Sites ◽

Nest Site Fidelity ◽

Males And Females

Abstract Nannophrys ceylonensis (Ranidae) is a terrestrial breeding anuran, found on wet vertical or near-vertical rock surfaces. Non-breeding adult males and females take refuge in separate crevices in the rock surfaces during the day and emerge at night to forage. Males can be polygynous; mating takes place inside crevices. Fathers exhibit paternal care for multiple clutches of eggs and guard eggs from predators. Paternal care of this species is obligatory; hatching success decreases without it. Females do not contribute to parental care. Males show nest site fidelity and defend territories against conspecifics. A scarcity of suitable nest sites may limit reproductive success in N. ceylonensis. Larvae hatch at Gosner stages 21-22 and leave their nests at stages 24-25 to live as truly terrestrial tadpoles, foraging on the rock surfaces near their natal nests.

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