From brooding to hatching: new insights from a female Octopus vulgaris in the wild

2015 ◽  
Vol 96 (6) ◽  
pp. 1341-1346 ◽  
Author(s):  
Manuel E. Garci ◽  
Jorge Hernández-Urcera ◽  
Miguel Gilcoto ◽  
Raquel Fernández-Gago ◽  
Ángel F. González ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Natural Habitat ◽  
Egg Laying ◽  
Laying Date ◽  
Octopus Vulgaris ◽  
Battery Life ◽  
Brooding Period ◽  
Data Loggers ◽  
In The Wild ◽  
Reproductive Events

A brooding Octopus vulgaris female was monitored for 128 days in her natural habitat. The main reproductive events and embryonic development in relation to the temperature inside the spawning den, which was recorded by long-battery-life mini-data loggers, are described in the wild. The den temperature ranged from 12.9 to 19.3°C. The total number of egg strings was 160, and the total number of eggs spawned ranged between 139,040 and 241,760 (mean 190,400). The brooding period, the egg laying interval and the duration of the hatching course lasted 128, 35 and 43 days, respectively. Both egg laying and hatching were intermittent processes. The time taken for embryonic development was variable (85–128 d) and depended on the laying date, temperature and position of the string in the egg cluster and the position of the egg in the egg string. The first hatching observed occurred after a progressive and gradual increase of the temperature from 14.9 to 19.3°C. The 280 min of video recordings taken by scuba divers showed that several times, this female opened and closed a small window in the obstructions of the den entrance to facilitate a way out for the hatchling batches.

Observations on the Embryonic Development of Octopus tetricus (Mollusca : Cephalopoda)

1978 ◽  
Vol 29 (1) ◽  
pp. 19 ◽  
Author(s):  
LM Joll
Keyword(s):  
Embryonic Development ◽  
Breeding Season ◽  
Wild Population ◽  
Yolk Sac ◽  
Egg Laying ◽  
Larvae And Juveniles ◽  
In The Wild

The development of O. tetricus embryos reared in the laboratory is described. The course of embryo-genesis is similar to that of O. vulgaris but the shape of stage-time plots differs. Most embryos undergo two reversions during development but failure to reverse does not prevent continued development. Both naturally and artificially hatched embryos still have the internal yolk sac, which is not fully absorbed until 4 or 5 days after hatchnig. Records of egg-laying in the laboratory and of the presence of larvae and juveniles in the wild population indicate that O. tetricus has a prolonged breeding season.

Experimental increase in female mass during the fertile phase leads to enhanced extra-pair paternity in pied flycatchers Ficedula hypoleuca

2019 ◽  
Author(s):  
Mireia Plaza ◽  
Alejandro Cantarero ◽  
Juan Moreno
Keyword(s):  
Negative Relationship ◽  
Ficedula Hypoleuca ◽  
Egg Laying ◽  
Female Dominance ◽  
Laying Date ◽  
Control Group ◽  
Wing Loading ◽  
Potential Fecundity ◽  
Fertile Phase ◽  
Extra Pair Paternity

Female mass in most altricial birds reaches its maximum during breeding at egg-laying, which coincides temporally with the fertile phase when extra-pair paternity (EPP) is determined. Higher mass at laying may have two different effects on EPP intensity. On the one hand, it would lead to increased wing loading (body mass/wing area), which may impair flight efficiency and thereby reduce female’s capacity to resist unwanted extra-pair male approaches (sexual conflict hypothesis). On the other hand, it would enhance female condition, favouring her capacity to evade mate-guarding and to search for extra-pair mates (female choice hypothesis). In both cases, higher female mass at laying may lead to enhanced EPP. To test this prediction, we reduced nest building effort by adding a completely constructed nest in an experimental group of female pied flycatchers (Ficedula hypoleuca). Our treatment caused an increase in mass and thereby wing loading and this was translated into a significantly higher EPP in the manipulated group compared with the control group as expected. There was also a significant negative relationship between EPP and laying date and the extent of the white wing patch, an index of female dominance. More body reserves at laying mean not only a higher potential fecundity but a higher level of EPP as well. This interaction had not previously received due attention but should be considered in future studies of avian breeding strategies.

scholarly journals Internal embryonic development in a non-copulatory, egg-laying teleost, the three-spined stickleback, Gasterosteus aculeatus

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Laura L. Dean ◽  
Shaun Robertson ◽  
Muayad Mahmud ◽  
Andrew D. C. MacColl
Keyword(s):  
Embryonic Development ◽  
Gasterosteus Aculeatus ◽  
Egg Laying

scholarly journals Group size and aquatic vegetation modulates male preferences for female shoals in wild zebrafish, Danio rerio

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aditya Ghoshal ◽  
Anuradha Bhat
Keyword(s):  
Group Size ◽  
Aquatic Vegetation ◽  
Natural Habitat ◽  
Ecological Factors ◽  
Choice Test ◽  
Female Group ◽  
Aquatic Flora ◽  
In The Wild ◽  
The Individual

AbstractShoaling decisions in the wild are determined by a combination of innate preferences of the individual along with the interplay of multiple ecological factors. In their natural habitat as well as in the laboratory, zebrafish is a shoaling fish. Here, we investigate the role of group size and associated vegetation in shaping shoaling preferences of wild male zebrafish. We studied the association preference of males to groups of female shoals in a multi-choice test design. We found that males made greater proportion of visits to an 8-female group compared to 2 and 4-female groups. However, males spent similar proportions of time across the three female-containing groups. When artificial vegetation was incorporated along with female number as an additional factor, we found that males prefer high and moderately vegetated patches compared to low or no-vegetation groups, irrespective of the number of females in these patches. Based on experiments using a novel multi-choice design, our results show that preference for group size can change due to interaction of two separate factors. This work is a first attempt to understand the role of aquatic flora in determining shoaling preferences in zebrafish, using an experimental paradigm consisting of a gradation in female and vegetation densities.

Predicting the Distribution of Sunda Pangolin (Manis javanica Desmarest, 1822) in Way Canguk Research Station, Bukit Barisan Selatan National Park, Lampung

2021 ◽  
Vol 6 (1) ◽  
pp. 58612
Author(s):  
Silvi Dwi Anasari ◽  
Wulan Pusparini ◽  
Noviar Andayani
Keyword(s):  
National Parks ◽  
National Park ◽  
Natural Habitat ◽  
Area Under The Curve ◽  
Canopy Cover ◽  
Research Station ◽  
Environment Variables ◽  
Presence Data ◽  
Manis Javanica ◽  
In The Wild

The distribution of a species can help guide the protection activities in their natural habitat. Conversely, the lack of information on this distribution makes the protection strategy of this species difficult. The research was conducted in Way Canguk Research Station, Bukit Barisan Selatan National Park from January until March 2018. The purposes of this research were to create a distribution prediction map of Sunda pangolin (Manis javanica) and estimating the environment variables that most influenced the probability of the distribution. Fourteen points of camera trap coordinates were used for presence data with nine types of environment variables such as elevation, slope, understorey, canopy cover, distance from roads, distance from rivers, distance from villages, food source, and distance from the threat. The result of maxent showed an Area Under the Curve (AUC) value of 0.909 categorized as very good. The highest probability of Sunda pangolin distributions was in the Pemerihan Resort and Way Haru Resort area, while the dominant environmental variables included the distance from the village, the canopy cover, and the distance from threat with the value 47.7; 25.85; and 15.8%, respectively. Prediction maps and environment variables can help to identify the population of Sunda pangolin in the wild and can provide input for the national parks to prioritize protection areas for Sunda pangolin from the increased poaching.

scholarly journals Reproductive biology of Ophiorrhiza caudata C.E.C.Fisch. (Rubiaceae), an endemic and endangered creeping perennial herb of the Western Ghats, India

2021 ◽  
Vol 13 (13) ◽  
pp. 20056-20065
Author(s):  
Maria Theresa ◽  
Appukuttan Kamalabai Sreekala ◽  
Jayalakshmi Mohanlal
Keyword(s):  
Seedling Establishment ◽  
Fruit Set ◽  
Floral Morphology ◽  
Climatic Factors ◽  
Monsoon Season ◽  
Natural Habitat ◽  
Flowering Phenology ◽  
Perennial Herb ◽  
In The Wild ◽  
The Western Ghats

Ophiorrhiza caudata is a creeping, perennial herb distributed along wet and shady areas. The species is distylous with two distinct floral morphs: pin and thrum. Flowering usually occurs during the monsoon season. No particular difference was noticed in the flowering phenology of the two morphs. Presently the species is self-incompatible, however, it shows a tendency towards intramorph compatibility. Fruit set is above 60% in open pollination and intermorph pollination. Bees and butterflies are the major pollinators. The pollen flow between the two floral morphs varies depending upon floral morphology and pollinators. Fruit is a bi-valved capsule which dehisces by a splashing drop mechanism. The seeds are very minute. The rate of seed germination and seedling establishment in the wild condition is very poor due to adverse climatic factors. Ophiorrhiza caudata is struggling for survival in its natural habitat, where habitat fragmentation, climatic factors and poor seedling establishment could account for its narrow distribution.

scholarly journals Realities of rarity: climatically and ecologically restricted, critically endangered Kandian Torrent Toads (Adenomus kandianus) breed en masse

2015 ◽  
Author(s):  
Madhava Meegaskumbura ◽  
Nayana Wijayathilaka ◽  
Nirodha Abayalath ◽  
Gayani Senevirathne
Keyword(s):  
Forest Cover ◽  
High Elevation ◽  
Habitat Associations ◽  
Egg Laying ◽  
Primary Forest ◽  
Isolated Populations ◽  
In The Wild ◽  
Suitable Habitats ◽  
Wide Geographic Distribution ◽  
Forest Habitats

Endemic to Sri Lanka, genus Adenomus contains two torrent-associated toad species whose ecology and natural history in the wild is virtually unknown. Adenomus kelaartii is relatively common, with a wide geographic distribution. Its sister species, A. kandianus, however, is restricted to two isolated populations in fast-disappearing montane and sub-montane forests. Formally declared extinct after not being recorded for over a century, a few A. kandianus were rediscovered in 2012 and redescribed as "the world's rarest toad". Here we report the results of a two-year study of the occurrence, habits and habitat associations of adult and larval A. kandianus using both general surveys and quadrat sampling. We show this to be a secretive species with a patchy distribution. Non-breeding female toads dwell in primary-forest habitats, but after heavy and sudden downpours they form large mating congregations in large streams. Amplexed pairs swim synchronously, enabling them to traverse fast currents. Egg-laying sites remain unknown, but the ability to dive and vocalize underwater, and characteristics of the eggs, suggest that they lay eggs in dark recesses of the stream. Tadpoles show microhabitat partitioning within the stream, with the greatest diversity of stages in slow-flowing rocky areas. The more robust stages possessing sucker discs exploit rocky-rapids, while metamorphic stages inhabit stream margins. We use DNA-barcoding to show the existence of two disparate toad populations. Distribution modeling with forest-cover layers added, predict a very small remaining area of suitable habitats. Conservation of this climatically and ecologically restricted species hinge largely on the preservation of high-elevation primary and riparian forests and unpolluted torrents.

scholarly journals Current Distribution and Status of Non-Native Freshwater Turtles in the Wild, Republic of Korea

2020 ◽  
Vol 12 (10) ◽  
pp. 4042 ◽  
Author(s):  
Kyo Soung Koo ◽  
Soorim Song ◽  
Jae Hyeok Choi ◽  
Ha-Cheol Sung
Keyword(s):  
Environmental Factors ◽  
Human Factors ◽  
Native Species ◽  
Natural Habitat ◽  
Republic Of Korea ◽  
Current Status ◽  
Human Populations ◽  
Freshwater Turtles ◽  
In The Wild ◽  
The Republic

Globally, an increase in the transportation and expansion of the pet market is the most important cause of the invasion of non-native species. Invasion of non-native species disturbs native ecosystems and leads to socio-economic problems. The pet trade involving turtles has been globally recognized as the route through which non-native species enter ecosystems. As a result, the invasion of non-native turtles worldwide is causing problems such as competition, predation, transmission of parasites, and hybridization with native turtles. Every year, both the number of non-native turtles imported as pets in the Republic of Korea and the number of introduced species found in the wild is increasing. However, the current status of non-native turtles in the wild is not well known, posing major challenges to their management. In this study, we aimed to determine the current status of non-native turtles introduced into the wild in Korea. We analyzed the factors associated with the detection and distribution of non-native turtles. In total, 1587 of non-native turtles (three families, six genera, and 13 species including subspecies) were found in 648 sites in Korea: Chelydra serpentina, Mauremys sinensis, Chrysemys picta bellii, Graptemys ouachitensis, G. pseudogeographica pseudogeographica, G. p. kohni, Pseudemys concinna, P. nelsoni, P. peninsularis, P. rubriventris, Trachemys scripta elegans, T. s. scripta, and T. s. troostii. There was relationship between the distribution of non-native turtles and environmental factors such as precipitation and temperature. Moreover, human factors such as number of human populations and size of region were significantly related with the distribution and number of non-native turtles. In conclusion, it is likely that human factors are associated with the influx of invasive turtles to the natural habitat, while the possibility of survival and adaption for the turtles is associated mainly with environmental factors. Our result will be an essential guideline not only for understanding the current status of non-native turtles in Korea, but also for establishing strategies for management and control.

The early bird catches the worm: age-specific arrival time influences reproductive performance in the White Stork Ciconia ciconia

Bird Study ◽  
2019 ◽  
Vol 66 (1) ◽  
pp. 121-129
Author(s):  
Bourhane-Eddine Belabed ◽  
Mohammed Athamnia ◽  
Laïd Touati ◽  
Farrah Samraoui ◽  
Abdennour Boucheker ◽  
...  
Keyword(s):  
Reproductive Performance ◽  
Age Groups ◽  
Egg Laying ◽  
White Stork ◽  
Laying Date ◽  
First Year ◽  
Arrival Date ◽  
Breeding Colony ◽  
Ciconia Ciconia ◽  
The Impact

<sec><title>Capsule</title>Age, arrival date and egg laying date are essentially closely related and determine reproductive performance in the White Stork Ciconia ciconia.</sec><sec><title>Aims</title>To describe the impact of age, arrival date and egg laying date on breeding success in the White Stork.</sec><sec><title>Methods</title>Ringing data from a White Stork breeding colony of 212 nests at Dréan, Algeria, were used to model the relationship between age, arrival date, laying date and reproductive performance. Seventy breeders that were individually colour-ringed as nestlings were monitored.</sec><sec><title>Results</title>Birds breeding on the periphery of the colony had significantly smaller nests and showed a tendency towards later laying dates, but they did not differ from centrally nesting birds in age or arrival date. First year birds did not breed and second year birds were significantly more likely than older age groups to occupy nests but fail to lay eggs. Older birds arrived earlier at the breeding colony and had a higher probability of initiating laying than younger birds. They also had a higher probability of nesting successfully and fledging a larger number of young.</sec><sec><title>Conclusion</title>Age determined arrival and laying dates and influenced breeding performance in the White Stork.</sec>

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