Mating behaviour of the orange mud crab, Scylla olivacea: The effect of sex ratio and stocking density on mating success

Studies of sexual selection in monogamous species have hitherto focused on sexual selection among males. Here, we provide empirical documentation that sexual selection can also act strongly on females in a natural population with a monogamous mating system. In our field-based genetic study of the monogamous Western Australian seahorse, Hippocampus subelongatus , sexual selection differentials and gradients show that females are under stronger sexual selection than males: mated females are larger than unmated ones, whereas mated and unmated males do not differ in size. In addition, the opportunity for sexual selection (variance in mating success divided by its mean squared) for females is almost three times that for males. These results, which seem to be generated by a combination of a male preference for larger females and a female-biased adult sex ratio, indicate that substantial sexual selection on females is a potentially important but under-appreciated evolutionary phenomenon in monogamous species.

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Operational sex ratio and paternal age sway mating and reproductive performance in Menochilus sexmaculatus (Coleoptera: Coccinellidae)

The Canadian Entomologist ◽

10.4039/tce.2020.14 ◽

2020 ◽

Vol 152 (3) ◽

pp. 298-310

Author(s):

Swati Saxena ◽

Geetanjali Mishra ◽

Omkar

Keyword(s):

Sex Ratio ◽

Reproductive Performance ◽

Mating Behaviour ◽

Age Groups ◽

Paternal Age ◽

Operational Sex Ratio ◽

Middle Aged ◽

Developmental Duration ◽

Development Duration ◽

Older Males

AbstractOperational sex ratio and paternal age are known to independently affect mating behaviour and reproductive performance. We conducted experiments to assess the effects of operational sex ratio and paternal age on mating, reproduction, and total development duration of Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae). Three male-biased sex ratios, no (1:1), modest (1:2), and extreme (1:5) competition treatments, were formed using young, middle-aged, and old males. The reproductive performance of M. sexmaculatus at all ages under extreme competition (1:5) surpassed the other two treatments. More competition among males decreased the time of commencement of mating and increased the duration of copulation. Females laid a greater number of eggs in extreme competition treatments. The operational sex ratio (irrespective of age) had no significant effect on the total developmental duration of offspring. Among different age groups, older males took more time to commence mating and mated for longer durations in all the sex ratio treatments. The number of eggs in the first clutch was lowest when females were mated with older males with increased offspring development duration. Thus, it can be concluded that male-biased sex ratio elevates the performance of M. sexmaculatus. Among different age groups, older males were poor performers than young and middle-aged males.

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Mating behaviour and mating success in woodfrogs Rana sylvatica

Animal Behaviour ◽

10.1016/s0003-3472(80)80130-8 ◽

1980 ◽

Vol 28 (3) ◽

pp. 705-716 ◽

Cited By ~ 94

Author(s):

Richard D. Howard

Keyword(s):

Mating Success ◽

Mating Behaviour ◽

Rana Sylvatica

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Sex ratio, mating behaviour and Wolbachia infections in a sheetweb spider

Biological Journal of the Linnean Society ◽

10.1111/j.1095-8312.2009.01247.x ◽

2009 ◽

Vol 98 (1) ◽

pp. 181-186 ◽

Cited By ~ 20

Author(s):

BENGT GUNNARSSON ◽

SARA L. GOODACRE ◽

GODFREY M. HEWITT

Keyword(s):

Sex Ratio ◽

Mating Behaviour

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Spawning behaviour and mating success in hybrids of silver bream (Blicca bjoerkna L.) and rudd (Scardinius erythrophthalmus L.) in an experimental environment

Animal Biology ◽

10.1163/15707563-00002399 ◽

2013 ◽

Vol 63 (2) ◽

pp. 119-130 ◽

Cited By ~ 1

Author(s):

Billy Nzau Matondo ◽

Michaël Ovidio ◽

Jean Claude Philippart ◽

Pascal Poncin

Keyword(s):

Food Consumption ◽

Mating Success ◽

Parental Species ◽

Mating Behaviour ◽

Survival Rates ◽

Spawning Ground ◽

Scardinius Erythrophthalmus ◽

Experimental Fish ◽

Spawning Behaviour ◽

Dry Food

The egg-release, mating, courting and aggressive acts for the spawning behaviour as well as the survival rates after spawning at stages of eyed embryos, viable hatchlings, and larvae to dry food consumption for the mating success were studied in cultured silver bream Blicca bjoerkna × rudd Scardinius erythrophthalmus hybrids at their first sexual maturity. Experiments were conducted in experimental environments simulating natural reproductive conditions of the parental species. Spawning behaviour was analysed over 1 day from 8.00 to 18.00 hours using a remote-controlled video. Mating success was assessed from eggs and hatched embryos collected on the spawning ground. The results showed that these hybrids exhibited all the reproductive behaviours of the parental species with significantly more courtship than mating. Each egg-release act was accompanied by mating behaviour, involving all the experimental males. A surprising aggressive behaviour was observed in one male which attacked all other experimental fish. Successful mating resulted in the presence of fertilized eggs, the production of hatched embryos in experiments, and the survival of larvae at the dry food consumption stage. However, the low viable hatchling rate observed could indicate a very low chance of survival for these hybrids in rivers in which the occurrence of post-F1 individuals may be more possible by backcrossing.

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Habitat Selection and Mating Success in a Mustelid

International Journal of Zoology ◽

10.1155/2011/159462 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Thierry Lodé

Keyword(s):

Habitat Selection ◽

Mating Success ◽

Evolutionary Ecology ◽

Mating Behaviour ◽

Species Conservation ◽

Mustela Putorius ◽

Key Factor ◽

Good Reproduction ◽

Lactating Females ◽

Habitat Avoidance

Habitat selection remains a poorly understood ecological process, but relating mating behaviour to pattern of habitat selection constitutes a fundamental issue both in evolutionary ecology and in biological conservation. From radiotelemetry protocol, habitat-induced variations in mating success were investigated in a solitary mustelid carnivore, the European polecatMustela putorius. Selection for marshy habitat was regarded as adaptive in that mating success was found greater using marches than other habitats. Males consorted with 1.3 females, revealing a low polygyny rate. Pregnant or lactating females selectively shifted to deciduous woods. That some habitat types may favour a good reproduction forms a key factor for species conservation and environmental management. Nevertheless, such as in various vertebrates, habitat requirements seem to be based on simple broad features of habitat, suggesting that habitat avoidance rather than habitat preference can explain polecat habitat predilection.

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Rearing of Mud Crab, Scylla tranquebarica Larvae with Different Stocking Densities

Omni-Akuatika ◽

10.20884/1.oa.2017.13.2.261 ◽

2017 ◽

Vol 13 (2) ◽

Author(s):

Gunarto Gunarto ◽

Sulaeman Sulaeman

Keyword(s):

Stocking Density ◽

Larval Rearing ◽

Life Stages ◽

Asian Countries ◽

Mud Crab ◽

Experimental Tank ◽

Fibre Glass ◽

Commercial Diet ◽

Stage Development ◽

Southeast Asian Countries

Mud crab (Scylla tranquebarica) is an important aquaculture species, especially in Southeast Asian Countries. However, the larval rearing of this species faces problems resulted in low survival caused not only by intensif canibalism but also by prolonged in larval rearing period. The stocking density during ealy life stages is proposed to influence the crablet production in the larvae rearing tanks. The objective of this research was to evaluate the effect of stocking densities on larval stage development and crablet production of mud crab, S. tranquebarica. Four different initial stocking densities of larvae were tested using 200 L fibre glass tank, namely: A). 30 ind,/L, B). 45 ind./L, C). 60 ind./L and D). 75 ind./L. Rotifer, Brachionus sp, and Artemia nauplii were fed to the larvae with additional commercial diet. Water exchanged in the rearing tank was performed since 7 days post hatching (dph) to 20 dph at a rate of 10 to 40%. Larvae from each experimental tank was sampled periodically (2 to 4 days interval) in order to calculate larvae population, larvae development index (LDI). Megalopa occurences index (MOI), and crablet production were also monitored. The result showed that the highest of LDI and MOI were obtained from treatment B and D which were significantly different (P<0.05) to the other treatments. Furthermore, the highest of crablet production was obtained from treatment D = 495.3+22.48 ind./tank, which was significantly higher (P<0.05) compared to treatment A (48.5+4.94 ind./tank), treatment B (167.5+10.61 ind./tank) and treatment C (218.33+10.41 ind./tank). Therefore, the stocking density of 75 ind./L is optimum for mud crab S. tranquebarica larvae and recommended to be applied for commercial larvae production in hatchery. Keyword: Production, crablet, stocking density, larvae, Scylla tranquebarica

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Reproductive biology of the orange mud crab Scylla olivacea (Herbst, 1796) from the Pichavaram mangroves of south-east India

Indian Journal of Fisheries ◽

10.21077/ijf.2019.66.1.82235-04 ◽

2019 ◽

Vol 66 (1) ◽

Author(s):

C. Viswanathan ◽

M. Pravinkumar ◽

T.V. Suresh ◽

V. Elumalai ◽

S.M. Raffi

Keyword(s):

Sex Ratio ◽

Size Distribution ◽

Reproductive Biology ◽

Sexual Maturity ◽

Carapace Width ◽

Distribution Analysis ◽

Mud Crab ◽

Indian Coast ◽

Ratio Size ◽

Commercially Important

The present study was conducted to assess the size distribution, sex ratio, size at first sexual maturity, fecundity and spawning season of the commercially important orange mud crab Scylla olivacea (Herbst, 1796) in Pichavaram mangroves in south-east India. This study is the first contribution to the knowledge of reproductive biology of S. olivacea from the Indian coast. Size distribution analysis in the fishery revealed the irrational exploitation of undersized S. olivacea. The estimated sex ratio deviated from equality, being 1:0.87, revealing a male domination. Size at first sexual maturity was determined to be 87 mm in carapace width (CW) in females. Fecundity ranged from 1.16 to 3.53 million in females of 76 to 135 mm CW. Breeding takes place year-round with a peak in pre-monsoon, indicating that it is a prolific breeder. Results revealed that immature individuals of S. olivacea contributed significantly to the catches and thus an effective management of the resource by framing minimum legal size is crucial so that the females are allowed to spawn at least once prior to capture.

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