Sex-specific differences in growth, mortality and migration support population resilience in the heavily exploited migratory marine teleost Mugil cephalus (Linnaeus 1758)

2018 ◽  
Vol 69 (3) ◽  
pp. 385 ◽  
Author(s):  
John Stewart ◽  
Anne-Marie Hegarty ◽  
Caitlin Young ◽  
Ashley M. Fowler
Keyword(s):  
Sustainable Management ◽  
Life History Traits ◽  
Mugil Cephalus ◽  
Spawning Migration ◽  
Swimming Ability ◽  
Skipped Spawning ◽  
Eastern Australia ◽  
And Migration ◽  
Number Of Males ◽  
Population Resilience

Understanding mechanisms supporting the resilience of exploited fish populations is fundamental to sustainable management. Herein we identify sex-specific differences in life history traits that confer resilience in the heavily exploited population of Mugil cephalus along eastern Australia. M. cephalus in this region emigrate from estuaries and undergo an annual northerly spawning migration that is dominated by males. Males mature, on average, at younger ages than females and were most abundant in the spawning migration at age-4, whereas females were most abundant at age-5. Females grew significantly faster and larger than males, with both sexes being aged up to 14 years. These sex-specific differences relate directly to the population stability of M. cephalus under the reproductive strategy of a spawning migration. Males participate in the spawning migration at younger ages and in greater numbers than females to ensure a sufficient number of males for successful spawning. Females partition more energy to growth than males, maturing and participating in the spawning migration at older ages and larger sizes. The larger body size of females is related to increased fecundity, increased survivorship and more efficient swimming ability. These traits, combined with population strategies of both delayed and skipped spawning, convey substantial resilience.

A model to estimate the annual production of roes (avgotaracho) of flathead mullet (Mugil cephalus) based on the spawning migration of species

2005 ◽  
Vol 75 (1-3) ◽  
pp. 138-148 ◽  
Author(s):  
George Katselis ◽  
Constantin Koutsikopoulos ◽  
Yiannis Rogdakis ◽  
Thanasis Lachanas ◽  
Evagelos Dimitriou ◽  
...  
Keyword(s):  
Mugil Cephalus ◽  
Spawning Migration ◽  
Annual Production

scholarly journals Linking life-history traits, spatial distribution and abundance of two species of lugworms to bait collection: A case study for sustainable management plan

2018 ◽  
Vol 140 ◽  
pp. 433-443 ◽  
Author(s):  
Lola De Cubber ◽  
Sébastien Lefebvre ◽  
Charline Fisseau ◽  
Vincent Cornille ◽  
Sylvie Marylène Gaudron
Keyword(s):  
Spatial Distribution ◽  
Life History ◽  
Sustainable Management ◽  
Life History Traits ◽  
Management Plan

Fate of applied phosphorus in an effluent-irrigated Pinus radiata plantation

Soil Research ◽  
1999 ◽  
Vol 37 (6) ◽  
pp. 1095 ◽  
Author(s):  
R. A. Falkiner ◽  
P. J. Polglase
Keyword(s):  
Pinus Radiata ◽  
Sorption Isotherms ◽  
Average Concentration ◽  
Organic P ◽  
Retention Capacity ◽  
Inorganic P ◽  
Eastern Australia ◽  
Soil Irrigation ◽  
And Migration ◽  
Total P

We examined the fate of applied phosphorus (P) in a young Pinus radiata plantation in south-eastern Australia, spray-irrigated with secondary-treated municipal effluent. Measurements included changes (before irrigation, and after 5 years) in total P, total organic P, total inorganic P, labile P, and sorption and desorption characteristics. During the first 5 years a total of 363 kg/ha of P was applied at an average concentration of 5.4 mg/L. Irrigation changed the forms and distribution of P throughout the profile (0–1 m). Increases in labile inorganic P (membrane-exchangeable, bicarbonate-extractable, and in soil solution) were confined mostly to the 0–0.5 m horizon, and wholly within the 0–0.7 m horizon. In addition, large amounts of organic P (204 kg/ha) were mineralised within the surface 0.7 m, due to stimulation of decomposer activity by increased soil water. Mineralisation, therefore, provided a significant and additional input of inorganic P to soil. Irrigation and P additions changed both the placement and curvature of soil sorption isotherms. Retention capacity (0–0.5 m), calculated from P sorption isotherms, decreased by 180 kg/ha. Desorbable P, determined by sequential extraction with dilute acid, increased by 184 kg/ha. Thus, these 2 independent methods of measuring the changes in exchangeable P gave the same result. Of the total inorganic P added to the soil (in effluent and mineralised), 25% remained in the exchangeable form; the rest was retained unavailable for short-term exchange and migration through soil. After 5 years, fluxes (kg/ha) of P in the 0–0.7 m horizon were: input in effluent less storage in vegetation (323), change in total organic P (–204), change in total inorganic P (517), net change in total P (313). Thus, 97% of the net amount of P added in effluent was recovered in the surface 0.7 m. Results have implications for the way in which P retention capacity is calculated under effluent irrigation.

scholarly journals Intensive monitoring suggests population oscillations and migration in wild boar Sus scrofa in the Pyrenees

2013 ◽  
Vol 36 (1) ◽  
pp. 79-88
Author(s):  
M. Sarasa ◽  
◽  
J.-A. Sarasa ◽  
Keyword(s):  
Wild Boar ◽  
Sus Scrofa ◽  
Sustainable Management ◽  
Western Europe ◽  
Mountain Range ◽  
Ecological Processes ◽  
Annual Variations ◽  
Hunting Bag ◽  
And Migration ◽  
Local Variability

As few studies have analysed local variability in populations of wild boar Sus scrofa in Western Europe in recent years, our understanding of ecological processes currently affecting this species is limited. To analyse questions regarding local variability in wild boar abundance, we used information from 442 traditional drive hunts monitored throughout eight hunting periods in the Pyrenees mountain range (Urdués, N Spain). Results showed temporal oscillations in abundance, and a non–linear decrease of 23% in the number of wild boar seen per drive hunt between 2004 and 2011. Numbers of dogs and hunters per drive hunt also affected indexes of wild boar abundance. Inter–annual variations in bag size may cause overestimations of variations in boar abundance and may even deviate from the population dynamics inferred from the number of wild boars seen per drive hunt. The multimodal patterns of wild boar abundance during the hunting periods suggest migrations in the Pyrenees. Our findings highlight the limitations of hunting bag statistics in wild boar. Further studies are required to guarantee information–based sustainable management of wild boar populations.

scholarly journals Invertebrates and fire—challenges and opportunities for conserving biodiversity

2012 ◽  
Vol 124 (1) ◽  
pp. 47
Author(s):  
Alan York
Keyword(s):  
Life History ◽  
Life History Traits ◽  
Fire Management ◽  
Vascular Plant ◽  
Natural Ecosystems ◽  
Terrestrial Invertebrates ◽  
Invertebrate Biodiversity ◽  
Composition And Structure ◽  
Eastern Australia ◽  
Challenges And Opportunities

Fires, whether planned or unplanned, impact upon a suite of organisms in natural ecosystems. Direct (short-term) and indirect (longer term) effects influence the composition and structure of invertebrate communities through the interaction of site history, characteristics of individual fire events and species life-history traits. Prediction of fire responses based on vascular plant species life-history traits, and the development of a functional classification based on shared traits, underpins current fire management in south-eastern Australia. Can a similar approach be developed for terrestrial invertebrates, or should we focus on utilising a framework based on surrogates developed around vegetation composition and structure, or taxonomic alternatives? This paper considers whether the use of surrogates offers promise as a strategy of dealing with the complexity of invertebrate biodiversity and associated issues surrounding fire management. It proposes a functional approach, based on species’ life-history traits, that can complement existing strategies; and identifies opportunities that have potential for resolving existing challenges in biodiversity conservation in fire-prone environments.

Regional differences in the reproductive parameters of the sparsely-spotted stingaree, Urolophus paucimaculatus, from south-eastern Australia

2014 ◽  
Vol 65 (11) ◽  
pp. 943 ◽  
Author(s):  
Fabian I. Trinnie ◽  
Terence I. Walker ◽  
Paul L. Jones ◽  
Laurie J. Laurenson
Keyword(s):  
Life History ◽  
Annual Cycle ◽  
Regional Differences ◽  
Life History Traits ◽  
Size At Maturity ◽  
Reproductive Parameters ◽  
Maternal Condition ◽  
South Eastern ◽  
Eastern Australia ◽  
South Eastern Australia

Whether spatial variation occurs in the life-history traits of chondrichthyan species is important to fisheries modelling and assessments. A study on the reproductive parameters of Urolophus paucimaculatus from four separate regions across south-eastern Australia found regional differences in maximum total length (TL), size-at-maturity, size-at-maternity and litter sizes. Inshore embayments (Port Phillip Bay (PPB) and Corner Inlet (CI)) appear to allow for larger TLs (females and males) than do offshore areas (Lakes Entrance (LE) and Western Bass Strait (WBS)). Size-at-maturity and size-at-maternity decreased across longitude from west (PPB) to east (LE) and seasonality of parturition and ovulation occurred earlier in PPB (August–October) than in LE (September–December). Maximum litter size correlated with maximum TL (six in PPB, five in each of CI and LE, and four in WBS). There was uncertainty in classifying females for maternal condition because the reproductive cycle appears to range from a continuous annual cycle to a non-continuous biennial cycle. Much of the uncertainty arises from the ambiguity of observation of non-pregnant mature females, which have either aborted through capture and handling, or are in a ‘resting year’ between pregnancies. Most likely, the majority are reproducing annually with an unknown proportion of females non-continuous and resting between pregnancies.

scholarly journals Dispersal and migration have contrasting effects on butterfly flight morphology and reproduction

2020 ◽  
Vol 16 (8) ◽  
pp. 20200393
Author(s):  
Vaishali Bhaumik ◽  
Krushnamegh Kunte
Keyword(s):  
Life History Traits ◽  
Butterfly Species ◽  
Reproductive Diapause ◽  
Long Distance ◽  
Fragmented Habitats ◽  
Egg Carrying ◽  
Trade Offs ◽  
Flight Morphology ◽  
And Migration ◽  
Extra Stress

Movement may fundamentally alter morphology and reproductive states in insects. In long-distance migrants, reproductive diapause is associated with trade-offs between diverse life-history traits such as flight morphology and lifespan. However, many non-diapausing insects engage in shorter resource-driven dispersals. How diapause and other reproductive states alter flight morphology in migrating versus dispersing insects is poorly understood. To find out, we compared flight morphology in different reproductive states of multiple butterfly species. We found that dispersers consisted of ovulating females with higher egg loads compared with non-dispersing females. This trend was in stark contrast with that of migrating female butterflies in reproductive diapause, which made substantially higher investment in flight tissue compared with reproductively active, non-migrating females. Thus, long-distance migration and shorter resource-driven dispersals had contrasting effects on flight morphology and egg loads. By contrast, male flight morphology was not affected by dispersal, migration or associated reproductive states. Thus, dispersal and migration affected resource allocation in flight and reproductive tissue in a sex-specific manner across relatively mobile versus non-dispersing individuals of different species. These findings suggest that dispersals between fragmented habitats may put extra stress on egg-carrying females by increasing their flight burdens.

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