scholarly journals Población y uso de hábitat del venado de páramo Odocoileus lasiotis (Artiodactyla: Cervidae) en Venezuela

2015 ◽  
pp. 817-820
Author(s):  
Misael Molina ◽  
José H Arias
Keyword(s):  
Sex Ratio ◽  
Social Communication ◽  
Vascular Plants ◽  
Group Composition ◽  
Costa Rican ◽  
Pacific Region ◽  
Reproductive Condition ◽  
Direct Observations ◽  
Acti Vity ◽  
Time Of Year

Direct observations of Paramo's white-taí1ed deer were made along transecl in the Mucubají area (Parque N acional Sierra N evada, Mérida, Venezuela). Sex ratio was two does per buck. Group composition varied with time of year and reproductive condition. The reproductive cycle was similar to that of lhe white-tailed deer from the Costa Rican dry Pacific region. Acti vity was maximum between 9 - 11 h and 15 - 17 h, and minimum al night. The deer feed on 13 species of vascular plants. (five families), and one of mushroom (Boletaceae: Agaricales). Fifteen plant species were used for shelter. Territory delimitation and signs for social communication were made primarily on gymnosperms (Cupressus and Pinus). Most deer were observed in terrain with slopes under 20% where the more complex and diverse vegetation associations exist.

Grouping patterns in warthogs, Phacochoerus africanus: is communal care of young enough to explain sociality?

Behaviour ◽  
2010 ◽  
Vol 147 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Mary Peacock ◽  
Angela White ◽  
Elissa Cameron
Keyword(s):  
Group Composition ◽  
Group Living ◽  
Living Will ◽  
Lifetime Reproductive Success ◽  
Adult Males ◽  
Trade Offs ◽  
Cooperatively Breeding ◽  
Phacochoerus Africanus ◽  
Time Of Year ◽  
Communal Rearing

AbstractGroup-living will evolve when individuals increase their lifetime reproductive success by joining with other individuals. In cooperatively breeding societies, individuals living in a group will participate in the communal rearing of young. Several factors can influence the evolutionary trade-offs of grouping and it is often unclear whether cooperative breeding is advantageous or is simply a by-product of selection acting on grouping behaviour. We used sightings of 1318 warthogs in 711 groups to investigate whether the advantages of sociality in the warthog differ depending on an individual's age, sex, reproductive state, or the time of year. Adult males only formed temporary associations with other individuals indicating that participation in a group was not advantageous. In contrast, yearlings were almost inevitably found in groups, regardless of their sex or time of year, suggesting any costs to sociality were outweighed by the benefits. Grouping in adult female warthogs was complex; adult females were more likely to form groups in the presence of juveniles and when juveniles were at their most vulnerable stage indicating that sociality in females could be partially explained by the benefits of communal care of young. However, other factors influenced female cooperation including group composition and the time of year.

Differential habitat use and reproductive patterns of frugivorous bats in tropical dry forest of northwestern Costa Rica

2001 ◽  
Vol 79 (9) ◽  
pp. 1626-1633 ◽  
Author(s):  
Kathryn E Stoner
Keyword(s):  
Costa Rica ◽  
Sex Ratio ◽  
Adult Female ◽  
Tropical Dry Forest ◽  
Dry Forest ◽  
Reproductive Condition ◽  
Age Classes ◽  
Carollia Perspicillata ◽  
Reproductive Patterns ◽  
Artibeus Jamaicensis

To determine if frugivorous bats in tropical dry forest differentially use a particular habitat and if this use is related to their reproductive patterns, I monitored populations from one site from January 1994 to January 1997 in Parque Nacional Palo Verde in northwestern Costa Rica. Abundance, reproductive condition, sex ratio, age-classes, and recapture data were compared across seasons and years. During 56 nights of sampling, 13 species of frugivores and 5 nectarivores were captured (N = 998). Carollia perspicillata, Artibeus jamaicensis, and Sturnira lilium were significantly more abundant in 1994 than in 1995 or 1996. Carollia perspicillata and A. jamaicensis were captured year-round, but there were peaks of abundance in the dry season and the middle of the rainy season. Sixteen percent of 244 adult female C. perspicillata and 20% of 87 A. jamaicensis were reproductive, principally in February through June. Forty-three percent of 28 adult female S. lilium were reproductive from February to June and in October and December. Fifty-four percent of 26 adult female Centurio senex were reproductive between December 1995 and February 1996. Few subadults were captured at this site. Sex ratios were significantly different across seasons for C. perspicillata and A. jamaicensis. Seventy-three C. perspicillata were recaptured and 25 (34%) of these were recaptured after more than 4 months. The results of this study indicate that the abundance of some tropical frugivorous bats varies between years and (or) over seasons at a particular site within tropical dry forest.

Interannual variability of sperm reserves and fecundity of primiparous females of the snow crab (Chionoecetes opilio) in relation to sex ratio

2002 ◽  
Vol 59 (12) ◽  
pp. 1932-1940 ◽  
Author(s):  
Bernard Sainte-Marie ◽  
Jean-Marie Sévigny ◽  
Mireille Carpentier
Keyword(s):  
Sex Ratio ◽  
Carapace Width ◽  
Weight Percent ◽  
Snow Crab ◽  
Adult Males ◽  
Reproductive Condition ◽  
Embryo Production ◽  
Potential Fecundity ◽  
Chionoecetes Opilio ◽  
Female Promiscuity

Demographics of adults and reproductive condition of primiparous (first brood) females of the snow crab (Chionoecetes opilio) were monitored annually from 1994 to 2002 at a fished site to investigate the possibility that sperm supply limits embryo production. Abundance of primipara fluctuated 533-fold because of a recruitment pulse, and this caused a large oscillation in the sex ratio of adult males to primipara. Annual mean of stored ejaculate weight (SL) and potential fecundity index (PF, clutch weight × percent fertilized eggs) adjusted to constant primipara carapace width ranged from 31 to 130 mg by spermatheca and from 1.97 to 3.43 g by clutch, respectively. Annual mean of SL and number of stored sperm (range 3.81 × 106 to 35.00 × 106 sperm by spermatheca) decreased when sex ratio decreased, probably because of a combined reduction of sperm allocation and female promiscuity. Annual mean PF was negatively correlated with abundance of small males, which may reflect egg losses during postoviposition matings. Although sociosexual context has a large impact on reproductive condition of primipara, the possibility that sperm supply limits embryo production could not be confirmed or excluded because of the complexity of snow crab mating behavior.

scholarly journals Changing trends in elephant camp management in northern Thailand and implications for welfare

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5996 ◽  
Author(s):  
Pakkanut Bansiddhi ◽  
Janine L. Brown ◽  
Chatchote Thitaram ◽  
Veerasak Punyapornwithaya ◽  
Chaleamchat Somgird ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Management Practices ◽  
Captive Breeding ◽  
Management Strategies ◽  
Demographic Shift ◽  
Northern Thailand ◽  
Work Activities ◽  
Direct Observations ◽  
Wide Range ◽  
Guidelines And Standards

Background Elephant camps are among the most attractive destinations in Thailand for tourists from many countries. A wide range of management strategies are used by these camps, which can have varied impacts on health and welfare of elephants. Methods This study surveyed 33 camps with 627 elephants in northern Thailand to quantify the types of management practices and work activities experienced by captive elephants. The survey consisted of an interview with camp owners, and direct observations of camp operations. Results Data revealed considerable variation in elephant demographics, work activities, elephant care (i.e., housing, restraint, nutrition, health care, and breeding), and mahout management among the camps. In general, older camps (those in existence for >16 years) were involved in more intensive activities, like riding with saddles and shows. By contrast, newer camps provided more one-on-one activities for tourists and elephants, and emphasized more intimate, relaxing experiences (e.g., feeding, bathing, walking) than entertainment. A demographic shift also was observed, with elephants 20 years of age and younger having a sex ratio closer to 1:1 compared to elephants in older age categories (1:4.1–1:9.8). Discussion Shifts in elephant management to less intensive activities were observed, which could have positive implications for elephant welfare. The shifting sex ratio suggests successful captive breeding is resulting in the birth of more males, which could present new welfare challenges in the future, because bulls can be more difficult to manage and socialize, and are more likely to be kept isolated during musth. Ultimately, the goal is to understand how camp activities affect welfare, and to develop science-based guidelines and standards to aid in the management of both male and female elephants used in tourism.

Ambient temperature drives sex ratio and presence of pregnant females of Anoura geoffroyi (Phyllostomidae) bats living in temperate forests

2019 ◽  
Vol 101 (1) ◽  
pp. 234-240
Author(s):  
Romeo A Saldaña-Vázquez ◽  
Jorge Ortega ◽  
José Antonio Guerrero ◽  
M Isabel Aiza-Reynoso ◽  
M Cristina MacSwiney G ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Ambient Temperature ◽  
Breeding Success ◽  
Temperate Forests ◽  
Prenatal Development ◽  
Reproductive Condition ◽  
Pregnant Females ◽  
Different Populations ◽  
Energetic Constraints ◽  
Anoura Geoffroyi

Abstract Phenology in animals is strongly influenced by seasonality that promotes changes in abundance of food resources and temperature. These changes may impose energetic constraints to organisms in certain seasons during the year, especially on those animals facing high energetic demands, such as nectarivorous bats. Seasonality in temperate forests could, therefore, promote migration of female nectarivorous bat to find warmer sites, thus enhancing breeding success. To test this hypothesis, we compared the proportion of females and the proportion of pregnant females of the nectarivorous bat Anoura geoffroyi, between months, in six different populations across temperate forests of Mexico. Bats were captured over a complete season cycle either with sweep or mist nets at the entrance or near their roosting caves, and their age, sex, and reproductive condition were recorded. We found that over 50% of bats present in the cave roosts across different populations in temperate forests of the Trans-Mexican Neovolcanic Belt of Mexico during the warmer and wetter months (April–September) were females, both pregnant and nonpregnant. In contrast, fewer than 30% of bats present in the roosting caves sampled in the colder and drier months (October–March) were females. In addition, we found that the temperature that favors the proportion of females at the studied sites was greater than 8°C. We concluded that seasonality affects sex ratio and phenology of A. geoffroyi in Mexican temperate forests. Our findings suggest females’ migrations to lowland warmer sites to improve prenatal development.

Relationships of Some Species of Digenea with the Marine Prosobranch Littorina littorea (L.) II. The Effect of Larval Digenea on the Reproductive Biology of L. littorea

1971 ◽  
Vol 45 (2-3) ◽  
pp. 145-159 ◽  
Author(s):  
E. M. Robson ◽  
I. C. Williams
Keyword(s):  
Sex Ratio ◽  
Breeding Season ◽  
Sex Reversal ◽  
Littorina Littorea ◽  
Breeding Cycle ◽  
Reproductive Condition ◽  
Initial Infection ◽  
The North ◽  
Breeding Cycles ◽  
The Common

1. 5250 specimens of the common periwinkle, Littorina littorea (L.), from Scalby Rocks on the North Yorkshire coast were examined from October 1966 to November 1967 and data obtained on the size, sex and reproductive condition of the periwinkles and their infections with four species of Digenea, namely Cryptocotyle lingua (Creplin, 1825), Renicola roscovita (Stunkard, 1932), Himasthla leptosoma (Creplin, 1829) and Cercaria lebouri Stunkard, 1932.2. The normal breeding cycle of uninfected L. littorea and the breeding cycles found in periwinkles infected with larval Digenea are described and discussed. Initial infection takes place mainly when periwinkles are spent after their first breeding season and though later damage to the gonad may prevent reproduction, the breeding potential of the periwinkle population at Scalby Rocks is unlikely to be affected seriously. There was no evidence of sex reversal in uninfected or infected L. littorea and the normal sex ratio is 1:1. The phenomenon of gigantism as a result of digenean infection is discussed with respect to L. littorea.

scholarly journals The reproductive season of scleractinian corals in Socotra, Yemen

F1000Research ◽  
2014 ◽  
Vol 3 ◽  
pp. 78
Author(s):  
Andrew H. Baird ◽  
David Abrego ◽  
Emily J. Howells ◽  
Vivian R. Cumbo
Keyword(s):  
Scleractinian Corals ◽  
Reproductive Season ◽  
Reproductive Condition ◽  
Economic Implications ◽  
Broadcast Spawning ◽  
Coral Spawning ◽  
Time Of Year

Determining when corals reproduce has clear management and economic implications. Here we document the reproductive condition of corals in the genus Acropora on the island of Socotra in Yemen during February 2014. Twenty percent of colonies (n = 143) contained mature gametes and 28% had immature gametes indicating that spawning will occur in both February and March in 2014, confirming previous anecdotal reports of coral spawning at this time in Socotra. Acropora typically reproduce in synchrony with many other broadcast spawning scleractinian corals, and we therefore predict that many other species are reproductively active at this time of year.

scholarly journals Stable carbon and nitrogen isotope ratios of surface food residues in pre-Columbian ceramics from the southern Pacific of Costa Rica as evidence of prehistoric human diets

2019 ◽  
Vol 11 (2) ◽  
pp. 89-97
Author(s):  
Maureen Sánchez P. ◽  
Sally P. Horn ◽  
Chad Steven Lane
Keyword(s):  
Costa Rica ◽  
Sediment Cores ◽  
Pollen Grains ◽  
Isotopic Analysis ◽  
Costa Rican ◽  
Cultivated Plants ◽  
Archaeological Sites ◽  
Pacific Region ◽  
The Past ◽  
Food Residues

Introduction: to understand and interpret the consumption of plants and animals by humans in the past requires the investigation of different lines of evidence. Identifiable macroscopic remains of plants and animals, for example seeds and bones, are frequently found at archaeological sites and provide key data on food resources. Their analysis is complemented by the study of pollen grains or phytoliths of cultivated plants within archaeological horizons or in sediment cores recovered from lakes and wetlands near archaeological sites. Another important source of information on human diets in the past consists of food residues preserved in or on artefacts excavated from archaeological sites. Objective: to examine food residues in archaeological pottery from coastal and interior sites in the southern Pacific region of Costa Rica. Methods: we focus on isotopic analysis of carbonized food residues preserved on the inner surfaces of ceramic pots, plates, and other ceramic pieces from archaeological excavations in the intermediate zone (elevations 500-1500m) and coastal zone of the southern Pacific region of Costa Rica. Isotopic analysis of surface food residues on pottery relies on the fact that stable isotopes of carbon (12C and 13C) and nitrogen (14N and 15N) in foods differ based on the photosynthetic pathway of plants and on trophic level. Results: in our analysis of material from twelve sites we found evidence of diets with high amounts of C4 plants (likely maize), legumes, herbivores, and mixtures, but we did not find robust evidence of food residues with isotopic signatures characteristic of reef animals and mollusks, even though some sites are shell mounds. Conclusion: our research represents one of the first studies of surface food residues from Costa Rican pottery, and indicates the potential for studies of this type to strengthen understanding of indigenous subsistence patterns through time and across Costa Rican archaeological regions.

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