Test of Biotic and Abiotic Environmental Determinants of Amphipod (Hyalella azteca) Preamplexus

1987 ◽  
Vol 44 (2) ◽  
pp. 478-482 ◽  
Author(s):  
R. L. France
Keyword(s):  
Reproductive Behavior ◽  
Habitat Heterogeneity ◽  
Activity Patterns ◽  
Hyalella Azteca ◽  
Evolutionary Strategies ◽  
Environmental Determinants ◽  
Mating Tactics ◽  
Abiotic Variables ◽  
Shield Lakes ◽  
Amphipod Density

Variation in reproductive behavior (preamplexus) of the amphipod Hyalella azteca among 10 Canadian Shield lakes in Ontario was positively correlated with water temperature, possibly through its influence on either activity patterns or diapausal endocrinology. Intensity of preamplexus was not correlated with other abiotic variables including lake pH, alkalinity, total phosphorus, or chlorophyll a concentration. Similarly, the complicated evolutionary "strategies" suggested by Strong involving alterations in optimal mating tactics in response to differences in intensity offish predation, amphipod density, or habitat heterogeneity did not occur in these lakes.

scholarly journals Reproductive behavior of White-tailed Kites (Elanus leucurus) in the Pampas of Argentina

2019 ◽  
Vol 27 (3) ◽  
pp. 153-157
Author(s):  
Alejandro V. Baladrón ◽  
Matilde Cavalli ◽  
Matías G. Pretelli ◽  
María S. Bó
Keyword(s):  
North America ◽  
Species Distribution ◽  
Reproductive Behavior ◽  
Activity Patterns ◽  
Behavioral Pattern ◽  
Nest Construction ◽  
Food Provisioning ◽  
Breeding Behavior ◽  
Time Activity ◽  
Nearctic Region

AbstractThe White-tailed Kite (Elanus leucurus) is a raptor that has been less studied in the Neotropics than in the Nearctic region, especially in relation to its reproductive behavior. In this study, we report information about the phenology and activity patterns of this raptor at the Pampas of Argentina. We found that White-tailed Kites have a prolonged breeding season, from October to May. Time-activity budgets of mating pairs indicated a pronounced division of roles in parental care between sexes. Females devoted most of their time to nest construction, incubation and chick care (80% of total time) and males to food provisioning and vigilance (70% of total time). We registered 11 cases of prey transfer from the male to the female. In four cases the transfer occurred in flight and in the remaining seven cases while individuals were perched. Our results agree with general patterns on breeding behavior of White-tailed Kites from North America, suggesting a consistent behavioral pattern throughout the species’ distribution.

Phenotypic correlates of mating success in the sand wasp Bembecinus quinquespinosus (Hymenoptera: Sphecidae)

1989 ◽  
Vol 67 (10) ◽  
pp. 2557-2568 ◽  
Author(s):  
Kevin M. O'Neill ◽  
Howard E. Evans ◽  
Ruth P. O'Neill
Keyword(s):  
Body Size ◽  
Mating Success ◽  
Activity Patterns ◽  
Alternative Tactics ◽  
Mating Tactics ◽  
Thermal Environments ◽  
Mean Size ◽  
Yellow Pigmentation ◽  
Selection For ◽  
Colour Patterns

Females of the sand wasp Bembecinus quinquespinosus nest in dense aggregations, the offspring emerging in great numbers the following year. Males display alternative mating tactics. Large males search and dig for females about to emerge from the ground. Mating success here is correlated with body size, primarily because larger males are better able to carry the female in flight away from the emergence area and avoid further harassment. The largest males, representing about one-quarter of the population, obtained over 90% of the matings initiated in the emergence area, whereas males below average in size were never successful there. Because some females leave the area without mating, a pool of virgins is available to small males, who patrol just outside the emergence area and intercept passing females. Males below average in size (and all females) are black with pale white bands on the abdomen. In males above mean size, the proportion of yellow pigmentation on the dorsal and lateral surfaces increases with body size. Males undertaking alternative tactics experience differing thermal environments. Yellow colouration was correlated with higher cuticular reflectance. Comparative evidence and differences in the activity patterns of males of different colour suggest that yellow pigmentation acts as a thermoregulatory mechanism allowing larger males to increase their tolerance of the high temperatures and solar radiation loads in the emergence area. We hypothesize that the mating tactics represent condition-dependent behavioural tactics, with flexibility maintained by sexual selection, and that the colour patterns represent condition-dependent morphological tactics, with the developmental response favoured by selection for thermoregulatory ability.

scholarly journals USING CALLING ACTIVITY TO PREDICT CALLING ACTIVITY

2015 ◽  
pp. 12-16
Author(s):  
Donald J. Brown ◽  
Todd M. Swannack ◽  
Michael R. J. Forstner
Keyword(s):  
Survey Data ◽  
Activity Patterns ◽  
Population Estimates ◽  
Sampling Effort ◽  
Sampling Efficiency ◽  
Breeding Sites ◽  
Calling Activity ◽  
Abiotic Variables ◽  
Toad Bufo

Understanding anuran calling activity patterns is important for maximizing efficiency and value of call survey data collection and analyses. Previous studies have primarily focused on identifying and quantifying abiotic variables that influence anuran calling activity, and investigating relationships between calling activity and population estimates. In this study we investigated the use of a predictor pond approach to guide call survey effort. In this approach, calling activity at a subset of breeding sites (e.g., ponds) is used as a predictor of calling activity at additional breeding sites, with the goal being to minimize sampling effort while simultaneously maximizing sampling efficiency. We explored the efficiency of this approach using call survey data collected on the endangered Houston Toad (Bufo [Anaxyrus] houstonensis) at 15 known breeding ponds over 9 survey years. We found that if calling activity at 3 predictor ponds was used to decide if additional call surveys would occur at the remaining 12 ponds, we would have hypothetically correctly assumed calling activity was not occurring at non-predictor ponds on 92.1% of survey nights, and we would have hypothetically detected 93.9% of the total number of detected individuals over the 9 survey years. We found the predictor pond approach performed well in our case study, and believe it could be a valuable tool for many anuran monitoring programs.

scholarly journals Flexible mating tactics and associated reproductive effort during the rutting season in male reindeer (Rangifer tarandus, L. 1758)

2015 ◽  
Vol 61 (5) ◽  
pp. 802-810 ◽  
Author(s):  
Eliana Pintus ◽  
Stefania Uccheddu ◽  
Knut H. Røed ◽  
Javier Pérez Gonzaléz ◽  
Juan Carranza ◽  
...  
Keyword(s):  
Breeding Season ◽  
Rangifer Tarandus ◽  
Reproductive Effort ◽  
Activity Patterns ◽  
Male Mating ◽  
Mating Effort ◽  
Costs And Benefits ◽  
Mating Tactics ◽  
Reproductive Tactics ◽  
Mating Group

Abstract Polygynous males can change their mating tactics across their lifetime, but information is scarce on the flexibility of this trait within a given season and the relative costs and benefits of using different tactics. Here, we monitored individually marked male reindeer Rangifer tarandus and classified their mating tactics as harem-defense, sneaking, or mixed. The costs of the male reproductive effort were assessed using both direct (i.e. percentage of body mass lost) and indirect measures (i.e. activity patterns such as feeding, standing, and walking), while mating group size and reproductive success were recorded as mating effort benefits. Our results show that reindeer males may switch between the harem-defense and sneaking tactics throughout the same breeding season, providing further support to the notion that reproductive tactics are flexible in ungulates. The costs and benefits of male mating effort vary according to the mating tactic, reaching the highest values in harem-holders and the lowest values in sneaking males. Moreover, males who switched between the sneaking tactic and the harem-defence tactic tended to achieve higher mating success than males who consistently used the least costly tactic. Indeed, all harem-holders successfully sired offspring, whereas only two out of three mixed-tactic males sired one calf, and sneaking males did not sire any calves. In conclusion, our results show that reindeer males can modulate their mating efforts during the same breeding season by switching between the most costly harem-defense tactic and the least costly sneaking tactic, suggesting individual solutions to the balance between reproductive effort and mating opportunities.

Environmental determinants of activity variation of an overlooked burrowing rodent: the Indian crested porcupine

Mammalia ◽  
2018 ◽  
Vol 82 (5) ◽  
pp. 449-459 ◽  
Author(s):  
Aditi Mukherjee ◽  
Honnavalli Nagaraj Kumara ◽  
Subramanian Bhupathy
Keyword(s):  
Time Allocation ◽  
Ecosystem Engineer ◽  
Activity Patterns ◽  
Lunar Phase ◽  
Environmental Determinants ◽  
Use Patterns ◽  
Ecological Importance ◽  
Rate Of Emergence ◽  
Relationship Of ◽  
Burrow Use

Abstract A study of the activity patterns, time allocation for each activity and variations in activities due to environmental alterations are necessary for understanding the biology of any species. This study investigates the relationship of micro-habitat and environmental conditions with seasonal and temporal activities of Indian crested porcupines (ICP) around their burrows in Keoladeo National Park (KNP), India. This species is considered as a problem species, often ignoring its ecological importance as an ecosystem engineer. Of the 39 sampled burrows, 58.97%, 38.46% and 83.78% were occupied in winter, summer and monsoon, respectively. The estimated porcupine density was 3.21±1.32SD individuals/km2, accounting for a population size of 65.89±27.15SD individuals. A seasonal shift in rate of emergence was observed in monsoon and winter, when ICP emerged earlier, significantly correlating with the sunset timings. The daily activity records of adult ICP outside burrow significantly peaked in January–February when they prepare the burrows for the gestation period of 90–112 days, followed by rearing of the offspring. The temporal activity significantly reduced in the full moon nights, perhaps to avoid predators. The study affirms that environmental determinants including the timings of sunrise, sunset and lunar phase significantly affect the variations in temporal activity and burrow use patterns of ICP.

scholarly journals Niche partitioning in an assemblage of granivorous rodents, and the challenge of community-level conservation

Oecologia ◽  
2022 ◽  
Author(s):  
Rachel Y. Chock ◽  
Debra M. Shier ◽  
Gregory F. Grether
Keyword(s):  
Habitat Heterogeneity ◽  
Resource Selection ◽  
Activity Patterns ◽  
Niche Partitioning ◽  
Natural Disturbance ◽  
Community Level ◽  
Ecological Data ◽  
Subordinate Species ◽  
Species Specific ◽  
Management Recommendations

AbstractCoexistence of competing species in the same foraging guild has long puzzled ecologists. In particular, how do small subordinate species persist with larger dominant competitors? This question becomes particularly important when conservation interventions, such as reintroduction or translocation, become necessary for the smaller species. Exclusion of dominant competitors might be necessary to establish populations of some endangered species. Ultimately, however, the goal should be to conserve whole communities. Determining how subordinate species escape competitive exclusion in intact communities could inform conservation decisions by clarifying the ecological conditions and processes required for coexistence at local or regional scales. We tested for spatial and temporal partitioning among six species of native, granivorous rodents using null models, and characterized the microhabitat of each species using resource-selection models. We found that the species’ nightly activity patterns are aggregated temporally but segregated spatially. As expected, we found clear evidence that the larger-bodied kangaroo rats drive spatial partitioning, but we also found species-specific microhabitat associations, which suggests that habitat heterogeneity is part of what enables these species to coexist. Restoration of natural disturbance regimes that create habitat heterogeneity, and selection of translocation sites without specific competitors, are among the management recommendations to consider in this case. More generally, this study highlights the need for a community-level approach to conservation and the usefulness of basic ecological data for guiding management decisions.

scholarly journals Does the habitat structure control the distribution and diversity of the Odonatofauna?

2015 ◽  
Vol 75 (3) ◽  
pp. 598-606 ◽  
Author(s):  
AM Souza ◽  
FNO Fogaça ◽  
AM Cunico ◽  
J Higuti
Keyword(s):  
Habitat Heterogeneity ◽  
Habitat Complexity ◽  
Habitat Structure ◽  
Biological Communities ◽  
Structure Control ◽  
Neotropical Streams ◽  
High Gamma ◽  
Abiotic Variables ◽  
Abundance And Diversity ◽  
The Impact

AbstractThe statement that the habitat complexity and structure govern the abundance and diversity of biological communities has been widely investigated. In this context, we assumed the hypothesis of habitat heterogeneity, that is, the higher habitat complexity leads to greater diversity of Odonata. In addition, we analyzed the influence of habitat structure on the distribution of this community, and evaluated the effects of abiotic variables. Odonata larvae were collected with sieves and by electrofishing in ten neotropical streams belonging to the Pirapó River basin. Forty species of Odonata were registered, which were distributed in eight families, Libellulidae stood out with the highest richness. The high gamma diversity and distribution of Odonata were associated with habitat heterogeneity in these streams. However, the abiotic variables also seem to affect the distribution of Odonata species, in view of the impact of the land use in the vicinity of streams.

scholarly journals Long term monitoring of the reproductive behavior of wild Chinese pangolin (Manis pentadactyla)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nick Ching-Min Sun ◽  
Kurtis Jai-Chyi Pei ◽  
Li-Yue Wu
Keyword(s):  
Reproductive Behavior ◽  
Maternal Separation ◽  
Post Partum ◽  
Activity Patterns ◽  
Camera Traps ◽  
Adult Males ◽  
In The Wild ◽  
Manis Pentadactyla ◽  
History Of ◽  
Almost All

AbstractObservations of Chinese pangolin (Manis pentadactyla) in the wild are extremely rare and challenging because of their nocturnal and cryptic activity patterns and low population density. The present article reported the first field observation in eastern Taiwan, from October 4, 2012 to June 16, 2016, on the reproductive behavior of the Chinese pangolin based on the monitoring of a female (LF28) using radiotelemetry and camera traps. During this period, LF28 aged from 1–4.5 years old and gave two single-births, both took place in early December, at 3 and 4 years old, respectively. We recorded the entire 157 days of the first nursing period from parturition to maternal separation. For the second infant, the gestation period was estimated to be around 150 days based on the evidence that the pregnancy started in early Jul. 2015 and the offspring was born on Dec. 9, 2015. During the entire nursing period, LF28 frequently moved the offspring from one nursing burrow to another staying various durations ranging from 1 day to more than 35 days, and almost all (= 15/16) of these burrows were located in the core (MCP75) of LF28’s home range. Started from the month of parturition and lasting throughout the whole nursing period, different adult males constantly visiting the nursing burrows were recorded. Mating behavior was recorded once outside the burrow in March, which provided evidence of the occurrence of post-partum estrus in this species. Delayed implantation was proposed based on the observation of a several months lag between copulation and the estimated pregnancy initiation date. The present study demonstrated the advantage of using remote technologies to learn the life history of resting fossorial species.

Measuring snake activity patterns: The influence of habitat heterogeneity on catchability

1996 ◽  
Vol 17 (1) ◽  
pp. 47-54 ◽  
Author(s):  
James R. Dixon ◽  
Martin J. Whiting ◽  
Brian D. Greene
Keyword(s):  
Habitat Heterogeneity ◽  
Activity Patterns ◽  
Large Lake ◽  
River Population ◽  
Future Studies ◽  
Water Snake ◽  
Habitat Differences ◽  
Central Texas ◽  
Activity Cycles ◽  
Two Populations

AbstractActivity patterns for two populations of the Concho water snake (Nerodia harteri paucimaculata) were studied in a large lake system in central Texas, USA, and compared to a river population. Trap data suggested different activity patterns for the two geographically proximate lake populations. Testing of the trap data using the program CAPTURE revealed differences in catchability rather than activity cycles. Based on these results, the apparent activity patterns for one of the lake sites was considered erroneous; and the differences in catchability were ascribed to habitat differences. It is suggested that future studies should incorporate a test of equal catchability when making interpopulational comparisons.

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