Contrary to vertebrates, less aggressive and more consistent individuals are common in disturbed habitats in the colonial spider Metabus gravidus (Araneae: Araneidae)

Behaviour ◽  
2021 ◽  
pp. 1-24
Author(s):  
Abby Daniel ◽  
Johel Chaves-Campos
Keyword(s):  
Costa Rica ◽  
Urban Area ◽  
Colony Size ◽  
Habitat Disturbance ◽  
Undisturbed Site ◽  
Behavioural Types ◽  
Undisturbed Forest ◽  
Disturbed Habitats ◽  
Disturbed Site

Abstract Habitat disturbance may affect average behavioural types and consistency/plasticity of behaviour. Studies with solitary vertebrates suggest that human-modified habitats may favour bolder, more aggressive and more plastic individuals. We evaluated whether wild colonial spiders, Metabus gravidus, vary in the magnitude, consistency and plasticity of boldness and aggressiveness between an undisturbed forest and an adjacent urban area in Monteverde, Costa Rica. Repeatability of aggressiveness was high at the disturbed site but moderate at the undisturbed site; repeatability of boldness was low at both sites. Individual and population plasticity was similar between sites for both behaviours. Aggressiveness decreases with increasing colony size at the disturbed site; this trend was not observed at the undisturbed site. Boldness did not change with colony size. In contrast to solitary animals, our results indicate that less aggressive and more consistent colonies may have an advantage living in human-disturbed habitats.

scholarly journals Habitat disturbance influences the skin microbiome of a rediscovered neotropical-montane frog

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Randall R. Jiménez ◽  
Gilbert Alvarado ◽  
José Sandoval ◽  
Simone Sommer
Keyword(s):  
Relative Abundance ◽  
Bacterial Communities ◽  
Environmental Changes ◽  
Defense Mechanism ◽  
Anthropogenic Activities ◽  
Habitat Disturbance ◽  
Amphibian Declines ◽  
Stress Factors ◽  
Skin Microbiome ◽  
Disturbed Habitats

Abstract Background The skin microbiome serves as a first line defense against pathogens in vertebrates. In amphibians, it has the potential to protect against the chytrid fungus Batrachochytrium dendrobatis (Bd), a likely agent of amphibian declines. Alteration of the microbiome associated with unfavorable environmental changes produced by anthropogenic activities may make the host more susceptible to pathogens. Some amphibian species that were thought to be “extinct” have been rediscovered years after population declines in the late 1980s probably due to evolved Bd-resistance and are now threatened by anthropogenic land-use changes. Understanding the effects of habitat disturbance on the host skin microbiome is relevant for understanding the health of these species, along with its susceptibility to pathogens such as Bd. Here, we investigate the influence of habitat alteration on the skin bacterial communities as well as specifically the putative Bd-inhibitory bacterial communities of the montane frog Lithobates vibicarius. This species, after years of not being observed, was rediscovered in small populations inhabiting undisturbed and disturbed landscapes, and with continuous presence of Bd. Results We found that cutaneous bacterial communities of tadpoles and adults differed between undisturbed and disturbed habitats. The adults from disturbed habitats exhibited greater community dispersion than those from undisturbed habitats. We observed a higher richness of putative Bd-inhibitory bacterial strains in adults from disturbed habitats than in those from undisturbed habitats, as well as a greater number of these potential protective bacteria with a high relative abundance. Conclusions Our findings support the microbial “Anna Karenina principle”, in which disturbance is hypothesized to cause greater microbial dispersion in communities, a so-called dysbiosis, which is a response of animal microbiomes to stress factors that decrease the ability of the host or its microbiome to regulate community composition. On the positive side, the high richness and relative abundance of putative Bd-inhibitory bacteria may indicate the development of a defense mechanism that enhances Bd-protection, attributed to a co-occurrence of more than 30-years of host and pathogen in these disturbed habitats. Our results provide important insight into the influence of human-modified landscapes on the skin microbiome and health implications of Bd-survivor species.

The diet of a forest-dependent frog species, Odorrana morafkai (Anura: Ranidae), in relation to habitat disturbance

2020 ◽  
Vol 41 (1) ◽  
pp. 29-41
Author(s):  
Duong Thi Thuy Le ◽  
Jodi J.L. Rowley ◽  
Dao Thi Anh Tran ◽  
Huy Duc Hoang
Keyword(s):  
Rainy Season ◽  
Prey Availability ◽  
Feeding Strategy ◽  
Habitat Disturbance ◽  
Habitat Modification ◽  
Prey Composition ◽  
Frog Species ◽  
Disturbed Habitats ◽  
The Impact ◽  
Prey Items

Abstract While deforestation is one of the greatest drivers of biodiversity loss, our understanding of the effects of habitat modification on species is limited. We investigated the diet of a forest-dwelling frog species, Morafka’s frog (Odorrana morafkai), in a highland forest in Vietnam in relation to habitat disturbance, sex and season. We surveyed the species at 45 sites in forest of varying disturbance and examined its diet using stomach flushing, estimating prey availability via trapping. We detected significantly fewer O. morafkai in highly disturbed habitats compared to moderately disturbed or non-disturbed habitats. We revealed that O. morafkai is a dietary generalist, identifying 28 prey types, primarily invertebrates. Prey composition, the number of prey items per stomach and prey volume per stomach did not vary between disturbance levels. Diet did not vary significantly between sexes, except that females had a higher prey volume. Prey composition in the species varied between seasons, with Coleoptera and Orthoptera dominating the diet in the rainy season and Lepidoptera in the dry season. The number of prey items per stomach and prey volume were significantly higher in the rainy season. There was a significant correlation between prey availability and diet composition. The low number of O. morafkai detected in highly disturbed habitats suggests that this habitat may not be optimal for the species, despite having a generalist feeding strategy and presumed high mobility. This study provides a window into the impact of an increasing threat, habitat disturbance, on forest-dependent amphibian species.

scholarly journals “Bee-Flower-People Relationships, Field Biologists, and Conservation in Northwest Urban Costa Rica and Beyond.”

Zoosymposia ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 18-28
Author(s):  
G. W. FRANKIE ◽  
R. E. COVILLE ◽  
J. C. PAWELE ◽  
C. C. JADALLAH ◽  
S. B. VINSON ◽  
...  
Keyword(s):  
Costa Rica ◽  
Urban Areas ◽  
Land Use Changes ◽  
Field Research ◽  
Urban Environments ◽  
Dry Forest ◽  
University Of California ◽  
Forest Region ◽  
Undisturbed Forest ◽  
The University

The forests of Costa Rica are rich in a wide variety of pollinator types and a very diverse flora that supports them.  Our research group from the University of California, Berkeley and Texas A & M University, College Station has been researching the ecology of one pollinator group, the bees, in the northwest Guanacaste dry forest region since 1969.  Much natural forest existed in this area when we first began the work.  But, many land use changes have occurred over the years to present day to the point that it is difficult to find tracts of undisturbed forest suitable for field research, especially those not affected by wildfires, which are now common.        Further, urban areas in the region continue to grow with increasing numbers of people populating the region.  In this paper we provide an overview of our past bee-flower work for a historical perspective, and then weave in people that have now become an obvious ecological component of current bee-flower relationships.  We also explore new questions that have become relevant through time, especially those related to researchers and potential conservation opportunities to share their stories with audiences that may extend their knowledge for practical use.  Finally, we propose that researchers plan to devote some of their precious time establishing relationships with people in conserving what is left of bee-flower relationships in urban environments in Guanacaste and beyond in the country.  Avenues for extending this knowledge are explored in this paper.

Response of the white-footed mouse (Peromyscus leucopus) to the transition between disturbed and undisturbed habitats

1989 ◽  
Vol 67 (2) ◽  
pp. 505-512 ◽  
Author(s):  
Alicia V. Linzey
Keyword(s):  
Peromyscus Leucopus ◽  
Demographic Characteristics ◽  
Range Data ◽  
Clear Cutting ◽  
Behavioral Interaction ◽  
Strip Mine ◽  
Disturbed Habitats ◽  
The Relationship ◽  
Disturbed Site ◽  
White Footed Mouse

The relationship between social behavior, demography, and habitat selection in the white-footed mouse (Peromyscus leucopus) was studied at the transition zone between disturbed (clear-cutting and strip-mine) and undisturbed (woodland) habitats. Demographic characteristics included a tendency toward overrepresentation of young mice (juvenile and subadults) in disturbed habitats and higher disappearance rates for young woodland males than for females. Home range data indicated that movements between habitats were minimal and mostly restricted to the ecotone. Behavioral interaction studies revealed that woodland mice were more likely to initiate contact and that mice from the clear-cutting responded by retreating or fleeing. During a reciprocal removal experiment, 43% of the resident population of the clear-cutting moved to woodland habitat after the original woodland population had been removed; no residents of woodland habitat moved to a disturbed site following removal. The suggestion that disturbed habitats serve as dispersal sinks for behaviorally subordinate individuals is supported by these data.

scholarly journals Stand-replacing disturbance does not directly alter the succession of Norway spruce regeneration on dead wood

2014 ◽  
Vol 60 (No. 10) ◽  
pp. 417-424 ◽  
Author(s):  
J. Červenka ◽  
R. Bače ◽  
M. Svoboda
Keyword(s):  
Growth Rate ◽  
Picea Abies ◽  
Norway Spruce ◽  
Dead Wood ◽  
Forest Succession ◽  
Undisturbed Site ◽  
The Bohemian Forest ◽  
Decaying Wood ◽  
Disturbed Site ◽  
Severe Disturbance

Density of regeneration in European subalpine Norway spruce (Picea abies) forests is typically low with regeneration primarily located on dead or decaying wood. The post-disturbance development of this regeneration is crucial for natural forest succession. The aim was to identify the influence of disturbance on regeneration on decaying logs immediately after a severe disturbance event. Study plots were established in two subalpine spruce forests: the first, an undisturbed site located in the Hrubý Jeseník Mts. and the second site in the Šumava Mts. that has experienced recent severe disturbance. Regeneration density increased between 2008 and 2011 by 7% (0.29 individuals per square meter of log) at the undisturbed site and by 33% (3.24 individuals per square meter of log) at the disturbed site. The increased regeneration density observed at the disturbed site was mostly associated with the smallest saplings. The highest increase in regeneration density was observed on logs with the largest diameters. Three years after severe disturbance caused 100% mortality of the parent stand in the Bohemian Forest, no significant effect was recorded on the growth rate and survival of established spruce saplings on dead wood.  

Contrasting Diaspore and Vegetation Attributes of Grasses From Natural and Disturbed Habitats in an Urban Eucalypt Forest Reserve

1993 ◽  
Vol 41 (6) ◽  
pp. 637 ◽  
Author(s):  
BM Odgers ◽  
RW Rogers
Keyword(s):  
Grass Species ◽  
Forest Species ◽  
Forest Reserve ◽  
Morphological Attributes ◽  
The Road ◽  
Eucalypt Forest ◽  
Disturbed Areas ◽  
Undisturbed Forest ◽  
Mowing Regime ◽  
Disturbed Habitats

Forty one species of grasses from a eucalypt forest reserve near Brisbane, Australia, were allocated to groups characteristic of undisturbed forest, regularly mown areas, and road banks. Morphological attributes of diaspores, height and growth habit of mature plants, species origin, flowering times and life history were determined for each species. Species characteristic of the mown areas had lighter diaspores than the forest gasses and did not possess awns; if a callus was present it was blunt and did not have antrorse hairs. Species from mown areas also differed from the forest species in being mainly short stoloniferous exotics which flowered for longer than the forest species. Species characteristic of the natural forest and road bank areas had diaspores of similar mass, similar diaspores attributes (awns, callus and antrorse hairs) and species of both habitats were mainly tall and tufted. The road bank species differed from the forest species in being mainly of exotic origin and in flowering for up to 9 months per year longer than the forest species. That grass species of mown areas successfully compete with forest species in mown areas may be because of a mowing regime which selects for short, mainly stoloniferous, species which have longer periods of diaspore production than the forest species. As road banks are not subjected to regular mowing, an extended pattern of flowering which ensures a continuous supply of diaspores may account for road bank species successfully competing with forest species in disturbed areas.

scholarly journals Trophic guild and forest type explain phyllostomid bat abundance variation from human habitat disturbance

2020 ◽  
Author(s):  
Jorge D. Carballo-Morales ◽  
Romeo A. Saldaña-Vázquez ◽  
Federico Villalobos
Keyword(s):  
Forest Type ◽  
Phylogenetic Signal ◽  
Habitat Disturbance ◽  
List Type ◽  
Trophic Guilds ◽  
Trophic Guild ◽  
Animal Populations ◽  
Human Habitat ◽  
Animal Feeding ◽  
Disturbed Habitats

AbstractThe loss of tropical forest cover caused by land-use change is causing a reduction in functional groups, such as trophic guilds. Phyllostomid bats (family Phyllostomidae) are essential in the Neotropics since they occupy up to six trophic guilds, and are pollinators, seed dispersers, and regulators of vertebrate and invertebrate populations. In this study, a series of meta-analyses were performed in order to analyse their response to habitat disturbance. Data were obtained through a comprehensive literature review whereby we measured the abundance of phyllostomid bats in disturbed habitats and conserved forests. We found that the abundance of phytophagous bats depends on the type of habitat disturbance and the type of forest where it occurs. On the other hand, animal-feeding bats reduce their abundance in any disturbed habitat regardless of disturbance type and forest type. No phylogenetic signal was found in the response of bats to habitat disturbance, nor was the response found to be dependent on the type of crop, the age of the secondary forest, or the distance to a conserved forest. These results demonstrate that feeding and the type of forest where the disturbance occurs are important aspects to understand the reduction of animal populations in the face of habitat destruction processes. This has implications on the conservation of species and their function in ecosystems.HighlightsNo phylogenetic signal was found in the abundance of bats in disturbed habitats.The abundance of bats in disturbed habitats depends on the trophic guild.Forest altitude influences the abundance of bats in disturbed habitats.Animal-feeding bats reduced their abundance in disturbed habitats regardless of disturbance type and forest type.

scholarly journals Assessment and Valuation of Commercially Important Bivalves and Gastropods within the Seagrass Beds of Laguindingan, Misamis Oriental and Rizal, Zamboanga del Norte, Philippines

2021 ◽  
Vol 6 ◽  
Author(s):  
Joshua Zalsos ◽  
◽  
Dan Arriesgado ◽  
Elgen Arriesgado ◽  
Rodrigo Acuña
Keyword(s):  
Diversity Index ◽  
Organic Load ◽  
Line Transect ◽  
Human Consumption ◽  
Seagrass Beds ◽  
Monetary Value ◽  
Disturbed Area ◽  
Undisturbed Site ◽  
Commercially Important ◽  
Disturbed Site

A study was conducted to assess the abundance and value of commercially important bivalves and gastropods within the seagrass beds of Laguindingan, Misamis Oriental and Rizal, Zamboanga del Norte, Mindanao, Philippines. The line transect method was used to assess the diversity of the bivalves and gastropods within the seagrass beds and coring was used in collecting sediment samples. Laguindingan was categorized as undisturbed site, while Rizal as disturbed site. The results identified three families of gastropods in undisturbed and thirteen families in disturbed, comprising a total of seven bivalves and six gastropods. Cyprea sp. Dominated in undisturbed area, while Anadara inequivalves dominated in disturbed area. The diversity index in disturbed (1.57) was greater than in undisturbed (0.88) probably due to high organic matter (2.56ppm) compared to the undisturbed area (1.92ppm). Ironically, the total volume of bivalves and gastropods production in disturbed area was higher at19.84 kg compared with2.23 kg in undisturbed. In terms of total monetary value, the undisturbed production could yield PHP 22,672.32 (USD 466.48) in an approximated area of 165 ha, while PHP 422,130.50 (USD 8,685.37) in 326 ha in the disturbed area. The study revealed that higher diversity resulted in higher production with greater monetary value derived from bivalves and gastropods in disturbed area contributed by higher organic load. Protection and management of the seagrass beds is likely most needed in both disturbed and undisturbed are as to support not only a robust but also a healthy production of shellfish fit for human consumption.

Microclimatic patterns correlate with the distribution of epiphyllous bryophytes in a tropical lowland rain forest in Costa Rica

2009 ◽  
Vol 25 (3) ◽  
pp. 321-330 ◽  
Author(s):  
Michaela Sonnleitner ◽  
Stefan Dullinger ◽  
Wolfgang Wanek ◽  
Harald Zechmeister
Keyword(s):  
Costa Rica ◽  
Relative Humidity ◽  
Species Composition ◽  
Light Availability ◽  
Tropical Rain Forests ◽  
Strong Response ◽  
Lowland Rain Forest ◽  
Species Analysis ◽  
Quantitative Analyses ◽  
Undisturbed Forest

Abstract:Quantitative analyses of the factors driving the distribution of bryophytes in the phyllosphere of tropical rain forests are rare. In this study we sampled epiphyllous bryophytes on two leaves of each of 57 individuals belonging to four phorophyte species (Asplundia pittieri, Carludovica drudei, Costus laevis and Dieffenbachia concinna) at three adjacent, but microclimatically varied sites in the Esquinas forest, Costa Rica. Microclimatic parameters and phorophyte identities were correlated to differences in cover, diversity and species composition of bryophyte assemblages by means of Kruskal–Wallis tests, non-metric multidimensional scaling and indicator species analysis. High relative humidity and in particular daily fluctuations in relative humidity proved to be the most important factors for epiphyll distribution suggesting severe constraints of epiphyll colonisation by pronounced humidity fluctuations. Differences in air temperature and light availability as well as phorophyte identity were only weakly correlated with bryophyte cover and diversity. However, species composition of epiphyllous assemblages was related to all microclimatic variables as well as to phorophyte identity. The strong response of epiphyllous bryophytes to even subtle microclimatic variations suggests that undisturbed forest canopies and their control on microclimate may be essential for the development of epiphyll communities.

scholarly journals High genotypic diversity of the reef-building coral Porites lobata (Scleractinia: Poritidae) in Isla del Coco National Park, Costa Rica

2017 ◽  
pp. 279-292
Author(s):  
Jennifer N. Boulay ◽  
Jorge Cortés ◽  
Jaime Nivia-Ruiz ◽  
Iliana B. Baums
Keyword(s):  
Costa Rica ◽  
Sexual Reproduction ◽  
Colony Size ◽  
National Park ◽  
Southern Oscillation ◽  
Genotypic Diversity ◽  
Physical Structure ◽  
Ecosystem Recovery ◽  
Relative Contribution ◽  
Porites Lobata

The isolated Isla del Coco experiences periodic, extreme disturbances which devastate coral reefs surrounding the island. Scleractinian corals build the physical structure of the reef therefore ecosystem recovery relies on coral species recovery. Coral recruits can be of sexual or asexual origin, and the relative success of the two recruit types influences the speed and spread of recovery processes. Here we focus on the massive coral, Porites lobata, because it is the main reef-builder around Isla del Coco to describe the relative contribution of asexual and sexual recruits to population maintenance. P. lobata samples were collected using a spatially explicit random sampling design in three plots at Isla del Coco: Punta Ulloa (n=17), Bahía Weston (n=20) and Punta María (n=20) and samples were genotyped with 11 microsatellite markers. Additional sampling was conducted at three “coastal” sites near the Costa Rican mainland (Isla del Caño Biological Reserve): Caño1 (n=8), Caño2 (n=10), Caño5 (n=11) to compare the contributions of asexual and sexual recruits at Isla del Coco sites to coastal sites. Isla del Coco sites were characterized by small colony size (>60% of colonies <0.5m2) and high sexual reproduction. Sites were either mostly or entirely sexual,consisting of only unique genotypes (NG/N= 0.90-1.00; G O/GE=0.83-1.00; D=0.99-1.00). Although there were no significant differences in genetic diversity (number of alleles per locus, number of private alleles) or colony size between Isla del Coco and the coastal sites, the coastal sites exhibited a greater range of genotypic diversity from moderately asexual (NG/N=0.5; GO/GE=0.36; D=0.8) to purely sexual (NG/N=1.0; GO/GE=1.0; D=1.0). The mode of asexual reproduction in P. lobata is likely fragmentation of adult colonies rather than asexual larval production because ramets of P. lobata occurred close together and asexually produced larvae have not been reported in gonochoric broadcast spawners like P. lobata. Frequent sexual reproduction at Isla del Coco National Park might represent a resource for rapid recovery following extreme El Niño-Southern Oscillation (ENSO) disturbance events. In contrast, larger, asexuallyproduced fragments rather than smaller, sexually-produced larvae appear to have the advantage at some coastal sites. The high frequency of sexual reproduction at Isla del Coco indicates that not only are sexual partners available but also current conditions are favorable for the delivery of larvae and the rate of predation on small larval recruits must be moderate. Citation: Boulay, J.N., J. Cortés, J. Nivia-Ruiz & I.B. Baums. 2012. High genotypic diversity of the reef-building coral Porites lobata (Scleractinia: Poritidae) in Isla del Coco National Park, Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 279-292. Epub 2012 Dec 01.

Sign in / Sign up

Export Citation Format

Share Document