scholarly journals Reproductive Ecology of Wrinkle-Lipped Free-Tailed Bats Chaerephon plicatus (Buchannan, 1800) in Relation to Guano Production in Cambodia

Diversity ◽  
2018 ◽  
Vol 10 (3) ◽  
pp. 91 ◽  
Author(s):  
Neil Furey ◽  
Paul Racey ◽  
Saveng Ith ◽  
Van Touch ◽  
Julien Cappelle
Keyword(s):  
Body Condition ◽  
Human Disturbance ◽  
Conservation Management ◽  
Population Monitoring ◽  
Dry Season ◽  
Reproductive Phenology ◽  
Wet Season ◽  
Energetic Stress ◽  
Breeding Cycles ◽  
Wildlife Populations

Wildlife populations in Southeast Asia are subject to increasing pressure from climate change, habitat loss and human disturbance. Cave-roosting bats are particularly vulnerable to all three factors. Because of the ecological services they provide, it is important to assess specific vulnerabilities to inform their conservation management. We evaluated the reproductive phenology and body condition of Chaerephon plicatus for 14 months in 2015–2016 and quantified guano harvesting at the largest colony in Cambodia in 2011–2016. As in Thailand and Myanmar, two annual breeding cycles were recorded, characterized as continuous bimodal polyoestry, with parturition primarily occurring in April and October. Significant declines occurred in body condition between the late wet season and the late dry season, suggesting that bats experience increasing energetic stress as the dry season progresses. Annual guano harvests increased over the study period but could not be used as a proxy for monitoring population size due to the loss of unknown amounts during the wet season and unquantified movements of bats between C. plicatus colonies in the region. We recommend studies to determine the scale and drivers of such movements and creation of sustainable guano harvesting and population monitoring initiatives to ensure the conservation of C. plicatus colonies in Cambodia.

Limited impact of irrigation on the phenology of Brachychiton megaphyllus: a deciduous shrub that flowers while leafless during the tropical dry season

2015 ◽  
Vol 31 (5) ◽  
pp. 459-467 ◽  
Author(s):  
Patricia J. Bate ◽  
Donald C. Franklin
Keyword(s):  
Soil Moisture ◽  
Reproductive Activity ◽  
Dry Season ◽  
Reproductive Phenology ◽  
Wet Season ◽  
Canopy Development ◽  
Seasonally Dry ◽  
Dry Tropics ◽  
Tap Root ◽  
Leaf Flush

Abstract:A suite of woody plants inhabiting the seasonally dry tropics flower while leafless during the dry season, raising intriguing questions about the role of moisture limitation in shaping their phenology. Brachychiton megaphyllus is one such species, a shrub of open forests and savannas in northern Australia. We documented leaf and reproductive phenology of 14 shrubs, and irrigated a further 15, to determine if soil moisture affected leafiness and reproductive activity. Brachychiton megaphyllus showed first flower buds shortly after the cessation of wet-season rains, and budded and flowered throughout the dry season. In some plants, leaf flush occurred prior to the first rains. Rates of fruit set and maturity were very low. Irrigation did not significantly influence leaf shoot or subsequent canopy development. Contrary to expectation, irrigation decreased the production of buds and flowers though it had no impact on the production of fruit, a response for which we suggest a number of hypotheses. Phenological responses to irrigation may have been limited because B. megaphyllus responds primarily to cues other than soil moisture and is buffered against seasonal drought by a large tap root. This suggests mechanisms by which flowering while leafless may occur in a range of species.

Prepartum supplementation effects on growth and fertility in Bos indicus-cross cows

1997 ◽  
Vol 37 (2) ◽  
pp. 141 ◽  
Author(s):  
G. Fordyce ◽  
L. A. Fitzpatrick ◽  
T. J. Mullins ◽  
N. J. Cooper ◽  
D. J. Reid ◽  
...  
Keyword(s):  
Body Condition ◽  
Post Partum ◽  
Bos Indicus ◽  
Late Pregnancy ◽  
Dry Season ◽  
Pregnancy Rates ◽  
Wet Season ◽  
Calf Growth ◽  
Treatment Groups ◽  
Calving Season

Summary. Three experiments were conducted in the dry tropics of north Australia using Bos indicus-cross cows. Cows in mid–late pregnancy were either unsupplemented during the late dry season or offered ad libitum (2 kg/day) molasses with 7.4% urea (w/w) (M8U) or cottonseed meal (1 kg/day) for up to 54 days commencing 2 months before the start of the calving season. Supplementation reduced weight loss in experiments 1 and 2 (P<0.05), but had no significant effect on weight or body condition in experiment 3. Supplementation had no effect on subsequent calf growth or cow lactation yields. Following early wet season rains in experiment 1, 9 and 49% of cows were ovulating 40 and 80 days post-partum, respectively, with no effect of supplementation. In experiment 2, 10 and 100% of cows had ovulated by 60 and 200 days post-partum, respectively. At any time between 80 and 180 days post-partum, supplemented cows were more likely to be cycling (P<0.05), independent of supplementation effects on weight or body condition. The average post-partum interval to oestrus was 30 days less in cows supplemented for 42 days (P = 0.08). In experiment 3, pregnancy rates in 1/2 and 3/4 Brahmans supplemented with M8U for 54 days (MU54) or whose calves were weaned at 2–3 months of age (WEAN) were 14% higher in the latter 2 months of mating than in cows supplemented for less than 40 days. Good seasonal conditions resulted in high pregnancy rates in all mature 5/8 Brahmans; when not weaned early, their average calving to conception interval (CCI) was 54 days (s.e. = 8.5 days). Pregnancy rates of first-lactation 5/8 Brahmans (average CCI of 125 days) supplemented for 39 days or less and weaned when calves averaged 6 months of age were 14–32% lower between 2 and 9 months post-partum than in contemporaries in the MU54 or WEAN treatment groups. It was concluded that dry-season supplementation of mid- to late-pregnant Bos indicus-cross cows with an energy concentrate for 42–54 days (‘spike’ feeding) may reduce post-partum anoestrus intervals via a mechanism which is not dependent on the effects on weight or body condition.

Ecology of the Northern Bettong, Bettongia tropica, a Tropical Mycophagist

1997 ◽  
Vol 24 (5) ◽  
pp. 549 ◽  
Author(s):  
C. N. Johnson ◽  
A. P. McIlwee
Keyword(s):  
Seasonal Variation ◽  
Body Condition ◽  
Forest Type ◽  
Dry Season ◽  
Wet Season ◽  
Hypogeous Fungi ◽  
Eucalyptus Forest ◽  
Seasonal Ecology ◽  
North Eastern ◽  
Open Woodland

The diet and seasonal ecology of the northern bettong, Bettongia tropica, was studied at three sites along a moisture gradient from closed Allocasuarina-Eucalyptus forest to dry open woodland in north-eastern Queensland. At each site, fungi (sporocarps of hypogeous ectomycorrhizal species) were the major food, and most of the remainder of the diet consisted of grass leaf and stem, roots and tubers, and lilies. Forbs and invertebrates were also eaten, but in small quantities. Fungus consumption was greatest at the wettest forest type and least at the driest site. Seasonal variation was insignificant except at the driest site, where fungus consumption peaked in the late wet season and dropped during the dry season; this seasonal fall in fungus consumption was associated with an increase in consumption of grass and roots and tubers. There was little seasonal variation in body condition, except at the driest site, where the dry-season decline in the proportional representation of fungus in the diet was associated with a decline in body condition. Breeding was continuous and aseasonal. B. tropica is found only in a narrow zone of sclerophyll forest along the western edge of wet tropical rainforest in north-eastern Queensland. We suggest that this species (like bettongs and potoroos in southern Australia) depends on hypogeous fungi, and that expansion of its geographical range into drier forest types is prevented by shortages of fungus during the dry season.

scholarly journals Timing of emergence and cave return, and duration of nocturnal activity in an endemic Malagasy fruit bat

2020 ◽  
Vol 33 (1) ◽  
Author(s):  
Riana V. Ramanantsalama ◽  
Steven M. Goodman
Keyword(s):  
Ecosystem Services ◽  
Body Condition ◽  
Dry Season ◽  
Adult Males ◽  
Nocturnal Activity ◽  
Wet Season ◽  
Fruit Bat ◽  
Adult Females ◽  
Narrow Passage ◽  
Age And Sex

Bats emerge from their day roost after dusk and different factors can affect the timing of departure, return, and duration of nocturnal activities. This study provides information on the time of emergence and return of an endemic Malagasy fruit bat, Rousettus madagascariensis, in a cave located in the Réserve Spéciale d’Ankarana, northern Madagascar. Individuals were captured in a narrow passage between the roost and cave exit and capture time for each individual was noted. Variation according to sex, age, and body condition, as well as the influence of season, and the sunset and sunrise time were analyzed. During the dry season, individuals started to emerge at 1913 hours and returned to the cave generally by 0505 hours; the duration of time outside the cave during the dry season was higher in adult females (0952 hours) followed by subadult males (0937 hours), sub-adult females (0931 hours), and adult males (0910 hours). During the wet season, individuals exited at 1926 hours and returned at 0351 hours; as in the dry season, adult females spent more time outside the cave (0833 hours), than sub-adult females (0800 hours), and adult males (0752 hours). The period of emergence varied according to the age and sex classes, and time of predawn return associated with the previous nocturnal activity. The period of return was influenced by season, and age and sex classes. Such information is useful to quantify shifts in bat ecology, especially for endemic species with limited distribution or those playing an important role in ecosystem services.

scholarly journals Seasonal changes in the reproductive performance in local cows receiving artificial insemination in the Pursat province of Cambodia

2020 ◽  
Vol 33 (12) ◽  
pp. 1922-1929
Author(s):  
Bengthay Tep ◽  
Yasuhiro Morita ◽  
Shuichi Matsuyama ◽  
Satoshi Ohkura ◽  
Naoko Inoue ◽  
...  
Keyword(s):  
Body Condition ◽  
Reproductive Performance ◽  
Artificial Insemination ◽  
Seasonal Changes ◽  
Dry Season ◽  
Ambient Conditions ◽  
Wet Season ◽  
Tropical Country ◽  
Calving Rate ◽  
Cool Dry Season

Objective: The present study aimed to survey seasonal changes in reproductive performance of local cows receiving artificial insemination (AI) in the Pursat province of Cambodia, a tropical country, to investigate if ambient conditions affect the reproductive performance of cows as to better understand the major problems regarding cattle production.Methods: The number of cows receiving AI, resultant number of calving, and calving rate were analyzed for those receiving the first AI from 2016 to 2017. The year was divided into three seasons: cool/dry (from November to February), hot/dry (from March to June), and wet (from July to October), based on the maximal temperature and rainfall in Pursat, to analyze the relationship between ambient conditions and the reproductive performance of cows. Body condition scores (BCS) and feeding schemes were also analyzed in these seasons.Results: The number of cows receiving AI was significantly higher in the cool/dry season than the wet season. The number of calving and calving rate were significantly higher in cows receiving AI in the cool/dry season compared with the hot/dry and wet seasons. The cows showed higher BCSs in the cool/dry season compared to the hot/dry and wet seasons probably due to the seasonal changes in the feeding schemes: these cows grazed on wild grasses in the cool/dry season but fed with a limited amount of grasses and straw in the hot/dry and wet seasons.Conclusion: The present study suggests that the low number of cows receiving AI, low number of calving, and low calving rate could be mainly due to poor body condition as a result of the poor feeding schemes during the hot/dry and wet seasons. The improvement of body condition by the refinement of feeding schemes may contribute to an increase in the reproductive performance in cows during the hot/dry and wet seasons in Cambodia.

Body condition and blood chemistry of agile wallabies (Macropus agilis) in the wet - dry tropics

2003 ◽  
Vol 30 (1) ◽  
pp. 59 ◽  
Author(s):  
Simon C. Stirrat
Keyword(s):  
Body Condition ◽  
Early Stage ◽  
Blood Chemistry ◽  
Serum Glucose ◽  
Dry Season ◽  
Cholesterol Concentration ◽  
Serum Chemistry ◽  
Leg Length ◽  
Wet Season ◽  
Dry Tropics

Seasonal differences in body condition, haematology and serum chemistry of agile wallabies (Macropus agilis) in the wet–dry tropics are described. The mass of wallabies caught in the dry season was lower than predicted for their body size (on the basis of leg length), indicating that they were in poorer condition in the dry season than in the wet season. Several haematology and serum chemistry values indicated that wallabies captured in the late dry season were in an early stage of undernutrition. Plasma and serum protein, serum albumin and serum urea concentrations, all indicators of recent protein intake, and packed cell volume and mean corpuscular volume were lower in the late dry season. However, the results for energy balance were inconclusive. Serum glucose concentration did not vary between seasons, while cholesterol concentration was lower and non-esterified fatty acid concentration was higher in the dry season. The wallabies foraged for a range of alternative food resources in the dry season, when preferred foods were scarce and of poorer quality. The results presented here indicate that although wallabies broadened their diet in the dry season, they were unable to maintain adequate nutritional intake to prevent loss of body condition.

scholarly journals The seasonal changes of the gut microbiome of the population living in traditional lifestyles are represented by characteristic species-level and functional-level SNP enrichment patterns

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Xue Zhu ◽  
Jiyue Qin ◽  
Chongyang Tan ◽  
Kang Ning
Keyword(s):  
Gut Microbiome ◽  
Seasonal Changes ◽  
Dry Season ◽  
Urban Setting ◽  
Snp Analysis ◽  
Wet Season ◽  
Human Gut ◽  
Human Gut Microbiome ◽  
Genome Level ◽  
Prevalent Species

Abstract Background Most studies investigating human gut microbiome dynamics are conducted on humans living in an urban setting. However, few studies have researched the gut microbiome of the populations living traditional lifestyles. These understudied populations are arguably better subjects in answering human-gut microbiome evolution because of their lower exposure to antibiotics and higher dependence on natural resources. Hadza hunter-gatherers in Tanzania have exhibited high biodiversity and seasonal patterns in their gut microbiome composition at the family level, where some taxa disappear in one season and reappear later. Such seasonal changes have been profiled, but the nucleotide changes remain unexplored at the genome level. Thus, it is still elusive how microbial communities change with seasonal changes at the genome level. Results In this study, we performed a strain-level single nucleotide polymorphism (SNP) analysis on 40 Hadza fecal metagenome samples spanning three seasons. With more SNP presented in the wet season, eight prevalent species have significant SNP enrichment with the increasing number of SNP calling by VarScan2, among which only three species have relatively high abundances. Eighty-three genes have the most SNP distributions between the wet season and dry season. Many of these genes are derived from Ruminococcus obeum, and mainly participated in metabolic pathways including carbon metabolism, pyruvate metabolism, and glycolysis. Conclusions Eight prevalent species have significant SNP enrichments with the increasing number of SNP, among which only Eubacterium biforme, Eubacterium hallii and Ruminococcus obeum have relatively high species abundances. Many genes in the microbiomes also presented characteristic SNP distributions between the wet season and the dry season. This implies that the seasonal changes might indirectly impact the mutation patterns for specific species and functions for the gut microbiome of the population that lives in traditional lifestyles through changing the diet in wet and dry seasons, indicating the role of these variants in these species’ adaptation to the changing environment and diets.

scholarly journals Seasonal Climate Impacts on Vocal Activity in Two Neotropical Nonpasserines

Diversity ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 319
Author(s):  
Cristian Pérez-Granados ◽  
Karl-L. Schuchmann
Keyword(s):  
Air Temperature ◽  
Daily Rainfall ◽  
Climatic Conditions ◽  
Dry Season ◽  
Climate Impacts ◽  
Calling Behavior ◽  
Wet Season ◽  
Focal Species ◽  
Calling Activity ◽  
Vocal Activity

Climatic conditions represent one of the main constraints that influence avian calling behavior. Here, we monitored the daily calling activity of the Undulated Tinamou (Crypturellus undulatus) and the Chaco Chachalaca (Ortalis canicollis) during the dry and wet seasons in the Brazilian Pantanal. We aimed to assess the effects of climate predictors on the vocal activity of these focal species and evaluate whether these effects may vary among seasons. Air temperature was positively associated with the daily calling activity of both species during the dry season. However, the vocal activity of both species was unrelated to air temperature during the wet season, when higher temperatures occur. Daily rainfall was positively related to the daily calling activity of both species during the dry season, when rainfall events are scarce and seem to act as a trigger for breeding phenology of the focal species. Nonetheless, air temperature was negatively associated with the daily calling activity of the Undulated Tinamou during the wet season, when rainfall was abundant. This study improves our understanding of the vocal behavior of tropical birds and their relationships with climate, but further research is needed to elucidate the mechanisms behind the associations found in our study.

scholarly journals Inorganic Nitrogen Production and Removal along the Sediment Gradient of a Stormwater Infiltration Basin

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 320
Author(s):  
Qianyao Si ◽  
Mary G. Lusk ◽  
Patrick W. Inglett
Keyword(s):  
Removal Efficiency ◽  
N Mineralization ◽  
Inorganic Nitrogen ◽  
Dry Season ◽  
Pollutant Removal ◽  
Net N Mineralization ◽  
Wet Season ◽  
Inorganic N ◽  
N Removal ◽  
Stormwater Infiltration

Stormwater infiltration basins (SIBs) are vegetated depressions that collect stormwater and allow it to infiltrate to underlying groundwater. Their pollutant removal efficiency is affected by the properties of the soils in which they are constructed. We assessed the soil nitrogen (N) cycle processes that produce and remove inorganic N in two urban SIBs, with the goal of further understanding the mechanisms that control N removal efficiency. We measured net N mineralization, nitrification, and potential denitrification in wet and dry seasons along a sedimentation gradient in two SIBs in the subtropical Tampa, Florida urban area. Net N mineralization was higher in the wet season than in the dry season; however, nitrification was higher in the dry season, providing a pool of highly mobile nitrate that would be susceptible to leaching during periodic dry season storms or with the onset of the following wet season. Denitrification decreased along the sediment gradient from the runoff inlet zone (up to 5.2 μg N/g h) to the outermost zone (up to 3.5 μg N/g h), providing significant spatial variation in inorganic N removal for the SIBs. Sediment accumulating around the inflow areas likely provided a carbon source, as well as maintained stable anaerobic conditions, which would enhance N removal.

scholarly journals Seasonal changes in water quality and macrophytes and the impact of cattle on tropical floodplain waterholes

2012 ◽  
Vol 63 (9) ◽  
pp. 788 ◽  
Author(s):  
N. E. Pettit ◽  
T. D. Jardine ◽  
S. K. Hamilton ◽  
V. Sinnamon ◽  
D. Valdez ◽  
...  
Keyword(s):  
Water Quality ◽  
Seasonal Changes ◽  
Aquatic Macrophyte ◽  
Plant Cover ◽  
Critical Role ◽  
Dry Season ◽  
Nutrient Concentrations ◽  
Wet Season ◽  
Dry Tropics ◽  
The Impact

The present study indicates the critical role of hydrologic connectivity in floodplain waterholes in the wet–dry tropics of northern Australia. These waterbodies provide dry-season refugia for plants and animals, are a hotspot of productivity, and are a critical part in the subsistence economy of many remote Aboriginal communities. We examined seasonal changes in water quality and aquatic plant cover of floodplain waterholes, and related changes to variation of waterhole depth and visitation by livestock. The waterholes showed declining water quality through the dry season, which was exacerbated by more frequent cattle usage as conditions became progressively drier, which also increased turbidity and nutrient concentrations. Aquatic macrophyte biomass was highest in the early dry season, and declined as the dry season progressed. Remaining macrophytes were flushed out by the first wet-season flows, although they quickly re-establish later during the wet season. Waterholes of greater depth were more resistant to the effects of cattle disturbance, and seasonal flushing of the waterholes with wet-season flooding homogenised the water quality and increased plant cover of previously disparate waterholes. Therefore, maintaining high levels of connectivity between the river and its floodplain is vital for the persistence of these waterholes.

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