Human-related Disturbances Research Articles

Recurrent wildfires alter forest structure and community composition of terra firme Amazonian forests

Abstract Wildfires associated with land-use and climate change have considered a key driver to the Amazon forest collapse. However, achieving a detailed understanding of how human-related disturbances impact forest successional trajectories needs comprehensive information spanning forest strata. Here, we investigate the impact of recurrent wildfires on forest structure, species diversity, and composition, making a comprehensive assessment of the regenerating, understory, and canopy tree communities in a sustainable use reserve in the eastern Amazon. Plant communities were described across 16 forest stands (old-growth, burned once and twice) sampling a total of 3620 individuals and 326 tree and palm species. Wildfires affected all attributes of forest structure. Aboveground biomass decreased by 44% in forest burned once, and 71% in twice-burned forest stands. Forest canopy was the most affected strata after the second fire, with a 44%-decrease compared to unburned forest. The same pattern emerged for basal area, which decreased by an average of 27.5% after the first fire and 53.8% following the second fire event. Overall, plant communities experienced a 50%-loss of species richness after two fires, including both dominant and rare species. Plant communities also became more dissimilar as fire events accumulated, with 58%–61% increase in species dissimilarity following two fires events. As wildfires reoccured, the old-growth forests of our focal landscape were converted into a mosaic of regenerating forest stands dominated by local short-lived pioneers (i.e. low-biomass early-regenerating forest stands) and a few tree species less sensitive to fire. Our findings highlight the urgent need to secure a resilient future for Amazonian forests with actions needed to support local livelihoods whilst reducing the prevalence of ignitions sources and allowing forest recovery.

Distinct drivers of bacterial community assembly processes in riverine islands in the middle and lower reaches of the Yangtze River.

Riverine islands are widespread alluvium wetlands developed in large rivers, and bacterial communities are crucial to their ecological function, yet their assembly processes are rarely addressed. The ecosystem services provided by the middle and the lower Yangtze are primarily threatened by pollution discharge from agricultural land use, and resource overutilization (e.g., embankments), respectively. Here, we assessed bacterial community assembly processes and their drivers within riverine islands in the middle Yangtze River (MR islands) and those in the lower reach (LR islands). A significant distance-decay relationship was observed, although the turnover rate was lower than that of the terrestrial ecosystem with less connectivity. Deterministic and stochastic processes jointly shaped community patterns, and the influence of stochastic increased from 26% in MR islands to 59% for those in LR islands. Meanwhile, the bacterial community in MR islands was controlled more by inorganic nitrogen availability, whereas those in LR islands were governed by pH and EC, although those factors explained a limited fraction of variation in the bacterial community. Potential indicator taxa (affiliated with Nocardioides and Lysobacter) characterized the waterway transport pollution. Overall, our study demonstrated that bacterial community dissimilarity and the importance of dispersal limitation increased concurrently along the flow direction, while distinct local factors further determined bacterial community compositions by selecting habitat-specificity taxa and particularly metabolism function. These findings enhanced our understanding of the mechanisms driving changes in bacterial communities of riverine islands subject to increased anthropogenic impacts.IMPORTANCERivers are among the most threatened ecosystems globally and face multiple stressors related to human activity. However, linkages between microbial diversity patterns and assembly processes in rivers remain unclear, especially in riverine islands developed in large rivers. Our findings reveal that distinct factors result in divergent bacterial community compositions and functional profiles in the riverine islands in the middle Yangtze and those in the lower Yangtze, with substantial differentiation in deterministic and stochastic processes that jointly contribute to bacterial community assemblages. Additionally, keystone species may play important metabolic roles in coping with human-related disturbances. This study provides an improved understanding of relationships between microbial diversity patterns and ecosystem functions under environmental changes in large river ecosystems.

Vessels Disturb Bottlenose Dolphin Behavior and Movement in an Active Ship Channel.

Although the Port of Corpus Christi, Texas, has become a top oil exporter, it is unknown if local dolphins are disturbed by high year-round vessel traffic. A shore-based digital theodolite and automatic identification system receiver were used to record data to assess common bottlenose dolphin (Tursiops truncatus) behavioral states and movement patterns in the Corpus Christi Ship Channel (CCSC) in relation to vessel traffic. Multinomial logistic regression and generalized additive models were applied to analyze the data. Vessels were present within 300 m of dolphins during 80% of dolphin observations. Dolphins frequently foraged (40%), traveled (24%), socialized (15%), and milled (14%), but rarely oriented against the current (7%) or rested (1% of observations). Season, time of day, group size, vessel type, vessel size, and number of vessels were significant predictors of dolphin behavioral state. Significant predictors of dolphin movement patterns included season, time of day, group size, calf presence, vessel type, and vessel numbers. The CCSC is an important foraging area for dolphins, yet the high level of industrial activity puts the dolphins at risk of human-related disturbance and injury. There is a crucial need to monitor the impact of increased anthropogenic influences on federally protected dolphins in the active CCSC, with broad application to dolphins in other ports.

Towards achieving a twenty-fold increase in the coverage of freshwater species distributions within protected areas in Europe

Freshwater ecosystems are threatened worldwide, with 1/3 of freshwater species being under extinction risk. Yet, systematic conservation planning has received little attention as a means to prioritize freshwater conservation areas. Here, we develop a comprehensive approach to spatially delineate key areas for freshwater conservation across Europe, considering directed-connectivity, climate change and human-related disturbances. We assess the adequacy of the current reserve network in protecting European freshwater ecosystems and provide guidelines for expansion. We conducted 13 prioritization scenarios for 18,300 sub-basins across Europe, accounting for the distribution of 1,668 freshwater species. Connectivity properties, metrics of climatic stability and human induced pressures were incorporated into the spatial prioritization framework. We highlight the critical importance of specific regions in Central and Southern Europe, the Mediterranean Basin, and parts of the Balkan Peninsula for future freshwater conservation efforts. However, our analysis also reveals the complete inadequacy of the current reserve network, as protected sub-basins only cover 4 % of the study area and encompass on average only 3 % of freshwater species distributions. In contrast, expanding current reserves to cover the top 17 % of high priority areas across Europe could substantially improve the overall coverage of species distributions, reaching an average of 61.5 % for all freshwater species and even exceeding 93.1 % for species of conservation interest (critically endangered, endangered and vulnerable species). The priority freshwater conservation network derived from the analysis provides specific spatial recommendations to help achieve conservation goals if the current reserve network is appropriately expanded.

Status of the Western Snowy Plover in Coastal Los Angeles and Orange Counties, California

From 2004 to 2021 we monitored the Western Snowy Plover (Charadrius nivosus nivosus) in coastal Los Angeles and Orange counties, California. Following an absence of 68 years, it returned to nest in 2017. Since then, the plovers have nested at three locations in Los Angeles County and four in Orange County, where numbers of nests at Anaheim Bay, Bolsa Chica State Beach, and Huntington State Beach increased. Protective beach management and nest enclosures presumably contributed to the increase of nests and hatching success at these sites. However, the number of nonbreeding Snowy Plovers in coastal Los Angeles County has declined, most steeply at Zuma Beach. At nonbreeding roosts in Orange County numbers at Balboa Beach and San Onofre State Beach declined, but countywide numbers were stable. All sites at which plovers roost experience human-related disturbance, which may include vehicles driving through them regularly, beach grooming that removes wrack and foraging resources, dogs chasing and flushing roosting plovers, and nearby large recreational events and summer camps as nonbreeding plovers return in July. Most sites lack consistent protective measures. Plover mortality has resulted from vehicle strikes and dogs. We recommend management that includes the establishment of special protection zones, restrictions on sand grooming, wrack removal, and vehicle traffic, and installation of protective enclosures around roost sites.

Local-scale habitat configuration makes a niche for wildlife encroaching into an urban landscape: grubbing sites of wild boar Sus scrofa in a city matrix

Urban environments may offer certain species diverse and abundant food resources of natural and anthropogenic origin. However, the local-scale configuration of habitats and urban infrastructure may influence foraging decisions regardless of the availability of food. In recent years, the expansion of wild boar Sus scrofa into areas significantly transformed by humans has been observed in many parts of its range. Grubbing (rooting) is a major foraging mode of the species, during which disturbance of the upper soil layers enables these animals to find and consume food items. However, the factors that determine the selection of grubbing sites in the urban landscape, where the balance between food availability and the avoidance of humans may influence foraging decisions, are not known. Our aim was to identify local-scale factors that influence grubbing site selection and the size of grubbed patches in an urban landscape. The characteristics of 108 wild boar grubbing sites in the city of Kraków (Poland) were compared to randomly selected control sites. The probable presence of a grubbing site was positively correlated with the proportion of meadows and fallow land in the vicinity and with increases in both canopy cover and distance to pavements. The size of a grubbed patch was positively correlated with the percentage of meadows in the vicinity, increasing distance to buildings and decreasing distance to pavements. We found a non-random pattern of grubbing sites in the urban landscape and indicated that the local-scale configuration of vegetation and urban infrastructure contribute to foraging site selection by wild boar. Our study highlights that the encroachment of wildlife into the urban landscape is a complex process, driven by both resource availability and the avoidance of human-related disturbances.

Fear in urban landscapes: conspecific flock size drives escape decisions in tropical birds.

Human-induced disturbances affect animal behaviours such as anti-predatory responses. Animals in urban environments tend to exhibit a reduced escape response, measured as a shorter flight initiation distance (FID), compared to their rural counterparts. While FID has been evaluated in animals dwelling in contrasting habitats (e.g. urban versus rural), little is known about how this response varies within urban environments, especially in tropical cities. Here, we studied the FID of 15 resident bird species in Bogota, Colombia, at 22 sites grouped into four categories (natural sites, metropolitan parks, zonal parks and residential areas) that differed in landscape features and evaluated which factors affected the escape responses of birds. We showed that birds foraging in larger flocks are more tolerant when being approached but they do not seem to be influenced by other factors such as heterospecific flock size, noise levels, pedestrian density, predator density, natural cover or body length. Also, birds inhabiting residential areas and parks showed a shorter FID compared to birds in natural areas suggesting that they are more tolerant of human-related disturbances compared to their conspecifics that live in natural areas within the city. Our study shows important differences in bird anti-predatory responses within the city and suggests that social strategies (i.e. flocking patterns) may be a mechanism for adapting to human-induced disturbances in urban tropical environments.

Managing wilderness? Holocene-scale, human-related disturbance dynamics as revealed in a remote, forested area in the Czech Republic

In the lowlands and uplands of Central Europe, which were inhabited continuously from the very start of the Holocene to the present times, it is difficult to find territories suitable for investigation of natural baselines. For this reason, we picked the complicated rocky terrain of one upland area in NE Bohemia called Adrspach because, based on the absence of archeological finds, it was supposed to have never been deforested or managed by people. The remote and inhospitable character of this particular area further encouraged this assumption. To our great surprise, however, high-resolution pollen analyses, supplemented by analyses of non-pollen palynomorphs and microscopic charcoals reveals that the local forest ecosystem had a dynamic development over entire Holocene. We were able to correlate this high-resolution understanding of vegetation successions with repeated fire disturbances. Was this fire disturbance dynamic natural? Subsequent archeological exploration and excavation in the area brought unexpected evidence, pointing to rather continuous human presence throughout most of the Holocene. From the Early Mesolithic to the Late Neolithic, available evidence suggests a hunter-gatherer mode of resource management. From the start of the Late-Holocene (ca 4 ka BP), the occurrence of coprophilous fungal spores and secondary anthropogenic pollen indicators suggest this area was impacted by recurrent domestic animal grazing. Testing this approach also in other remote forested areas of Central Europe, we argue, can have far-reaching implications for understanding long term human-environment agency by transforming our understanding of alternative subsistence and land use strategies during prehistory. At the same time, this can significantly alter existing concepts used in Central European nature conservation strategies, which tend to be based on an underlying assumption that our work challenges – the survival of little impacted wilderness at the Holocene scale.

Impact of climate and management on radial growth dynamics of two coexisting Mediterranean Quercus species in south Albania

In the context of changing climate conditions, it is crucial to understand how trees maintain resistance and resilience to and recover from drought stress and management-related disturbances, and how management (intensive/extensive) modulates tree growth responses to climate. Dendrochronological methods were used to examine radial growth rates, to reconstruct disturbance history and to evaluate growth resistance and resilience to and recovery from disturbance events identified by pointer year analysis in two coexisting Quercus species (Q. macrolepis Kotschy and Q. trojana Webb). Moreover, a dendro-ecological approach was used to quantify climate–growth relationships, including a drought index, the Standardised Precipitation Index (SPI). Q. trojana/Q. macrolepis showed major/moderate growth releases and moderate growth suppression. Q. trojana demonstrated statistically lower growth recovery than Q. macrolepis. The climatic drivers of radial growth in Q. macrolepis were May, June, September precipitation, July temperatures and the SPI accumulated since the previous year (up to 18 months); whereas Q. trojana responded significantly to May and June precipitation, July temperatures and the SPI at mid-time scales (< 8 months). Under intensive management, both species were more responsive to precipitation, temperature and short to mid-time scale SPI than during the extensive management period where they showed loss of sensitivity to spring–summer precipitation, temperature and SPI. These results are relevant to understand species vulnerability to climate and management/ human-related disturbances, and the effects of intensive/extensive management in modulating climate (drought)–growth relationships in Q. macrolepis and Q. trojana trees.

Are there Sexual Differences in the Autumn Food Habits of Raccoon Dogs (Nyctereutes procyonoides) in Suburban Area?

We studied the autumn (September–November) food habits of the raccoon dog (Nyctereutes procyonoides) by sampling the stomach contents of 64 individuals (male, n = 31; female, n = 33) killed on national roads in Ibaraki Prefecture. Our aim was to examine sex differences in the autumn food habits of raccoon dogs in suburban area where human related disturbances can occur on the raccoon dogs. The frequency of occurrence (FO) and the percent volume (PV) of fruits and insects were high for both males and females and FO and PV of garbage were low for both males and females. There were no significant differences between the sexes for food items. FO and PV were not significantly different between sexes for adults and yearlings. This is likely because males and females may use the same area even in suburban area, and they likely both forage on the most abundant food resources that are easily accessible within their habitats.

High Species Richness and Extremely Low Abundance of Cumacean Communities Along the Shelf and Slope of the Gulf of Guinea (West Africa)

The Gulf of Guinea belongs to the most scarcely sampled marine basins in the oceans of the world. We have analyzed diversity and distribution patterns of cumacean communities on the shelf and slope, along the coast of Ghana. The material was collected in October and November of 2012 using a van Veen grab (0.1 m2) on nine transects. Six stations were located at each transect (25, 50, 100, 250, 500, and 1,000 m). Sixty-three species of Cumacea were recorded withLeuconandEocumaas the most speciose genera, with 12 and eight species, respectively. Comparisons of species richness with literature data pointed that the Ghanaian coast hosts very diverse communities. About 95% of species were new to science, and the number of cumacean species known from the West Africa increased by over 100%. Nevertheless, most of the species had extremely low abundance, 13 singletons and 15 doubletons were found. Mean density of cumaceans was estimated at only 1.5 ind./0.1 m2. Species accumulation curve did not reach the asymptotic level, suggesting undersampling, despite the fact that sampling effort was high (250 samples). The highest species richness was recorded in the inner shelf (25–50 m) and on the slope (1,000 m). Cluster analysis separated shallow water communities from deeper regions on the shelf and upper slope. The most unique species composition was found at 1,000 m. Principal component analysis showed the importance of oxygen, sediments, and human-related disturbance for distribution of cumacean communities. In the shallows, oxygen content and presence of gravel were the most important factors structuring communities. In the deeper bottom areas (250–1,000 m), cumacean fauna was affected by local pollution, mainly by higher concentration of barium, other heavy metals, and THC.

Hydrochemical indicators of water source and contamination in fen peatlands of varying hydrogeomorphic settings in northern and central Poland

In this study, we considered 41 fens located in northern and central Poland. In our main hypothesis, we assumed that the base chemical composition of fen waters primarily depends on the hydrological regime, indicating a relationship to morphogenetic type of fen. We analyzed 40 physicochemical parameters of peatland porewater samples and discussed the relation of water chemistry with the hydrological and morphogenetic conditions of the individual fens. Further, we considered the additional factors that could significantly modify water chemistry. Physicochemical and hydrological parameters indicated a large diversity in habitat conditions among the investigated fens. Parameters significantly differentiating the examined objects were the concentrations of basic anions and cations and the associated electrolytic conductivity. Higher ion concentrations indicated a greater share of groundwater in the recharge of the investigated wetlands. Fens having a greater inflow of groundwater were characterized primarily by higher concentrations of calcium, bicarbonates and electrolytic conductivity, and were usually associated with tunnel and melt-out valleys. However, in some cases, the higher electrolytic conductivity resulted from anthropogenic pollution. Therefore, the use of indicators to separate such anthropogenically influenced sites from those naturally enriched in basic ions is crucial. Moreover, human-related disturbance of fen ecosystems were also demonstrated by elevated concentrations of certain metals and nutrients. We found that the processes responsible for the mobilization and inflow of metals played a secondary role in the diversification of the chemical composition of the waters of the investigated fens.

A C-vine copula framework to predict daily water temperature in the Yangtze River

The thermal regime of rivers plays a crucial role in chemical, biological and ecological processes. Effectively predicting water temperature is a key issue related to environment management. This study develops a probabilistic model based on C-vine copulas for water temperature prediction. The proposed framework is applied to forecast daily water temperature in the Yangtze River, considering long-term effects of preceding air temperature and daily discharge. The prediction performance of this framework is compared with the logistic regression model (LogR) and generalized regression neural network (GRNN). The results of this study indicate that the proposed C-vine copula framework and GRNN model provide better forecasting of stream temperature with weak human-related disturbances than LogR model. The outperformance of C-vine framework is reflected by its ability to accurately capture variations in the water temperature greatly affected by the Three Gorges Reservoir (TGR). This steady and reliable framework is further applied for the conservation of Chinese Sturgeon to estimate the range of suggested discharge, given the daily air temperatures, to adjust the water temperature within 18–20 °C at Yichang station during the spawning season. This application is verified to be more effective, providing indications for reservoir management to lower water temperatures by regulating river flow to ensure the occurrence of spawning activities. The results of this study may provide a scientific reference for the ecological operation of reservoirs in regulated rivers.

Seeing the wood despite the trees: Exploring human disturbance impact on plant diversity, community structure, and standing biomass in fragmented high Andean forests.

High Andean forests harbor a remarkably high biodiversity and play a key role in providing vital ecosystem services for neighboring cities and settlements. However, they are among the most fragmented and threatened ecosystems in the neotropics. To preserve their unique biodiversity, a deeper understanding of the effects of anthropogenic perturbations on them is urgently needed. Here, we characterized the plant communities of high Andean forest remnants in the hinterland of Bogotá in 32 0.04 ha plots. We assessed the woody vegetation and sampled the understory and epiphytic cover. We gathered data on compositional and structural parameters and compiled a broad array of variables related to anthropogenic disturbance, ranging from local to landscape‐wide metrics. We also assessed phylogenetic diversity and functional diversity. We employed nonmetric multidimensional scaling (NMDS) to select meaningful variables in a first step of the analysis. Then, we performed partial redundancy analysis (pRDA) and generalized linear models (GLMs) in order to test how selected environmental and anthropogenic variables are affecting the composition, diversity, and aboveground biomass of these forests. Identified woody vegetation and understory layer communities were characterized by differences in elevation, temperature, and relative humidity, but were also related to different levels of human influence. We found that the increase of human‐related disturbance resulted in less phylogenetic diversity and in the phylogenetic clustering of the woody vegetation and in lower aboveground biomass (AGB) values. As to the understory, disturbance was associated with a higher diversity, jointly with a higher phylogenetic dispersion. The most relevant disturbance predictors identified here were as follows: edge effect, proximity of cattle, minimum fragment age, and median patch size. Interestingly, AGB was efficiently predicted by the proportion of late successional species. We therefore recommend the use of AGB and abundance of late successional species as indicators of human disturbance on high Andean forests.

Assessing the Influence of Physical Factors and Human-Related Disturbances on Forested Wetland Communities in Georgia

Forested wetlands act as buffers between human civilization and aquatic ecosystems, providing numerous services. Due to widespread human influence, most existing forested wetlands are secondary forests. This study investigated 3 forested wetlands in the Oconee basin in middle Georgia to assess the influence of physical factors and anthropogenic disturbances on the tree composition. Our analyses revealed that the northernmost wetland had experienced the most recent major anthropogenic disturbance based on the dominance of an early successional species. The southernmost site, a floodplain forest, was the most diverse due to the short flooding durations that support a larger suite of species. The middle site was the least diverse but had the largest trees and total basal area.

Comparison of multiple behavioral traits between urban and rural squirrels

Recent rapid urbanization has imposed novel challenges to animals. Urban animals alter their behaviors such as increased boldness, exploration, and aggressiveness to cope with anthropogenic disturbance. However, most previous studies were highly biased toward birds and examined a limited number of behavioral traits, often employing species-specific methods. Thus, we still do not fully understand how other taxa behaviorally adjust to urbanization. In this study, we investigated multiple behavioral traits between urban and rural Eurasian red squirrels, Sciurus vulgaris, which is one of the typical urban colonizers across northern Eurasia. The open field test (OFT) and mirror image stimulation (MIS), two well-established methods for quantifying animal personality, were employed for behavioral comparisons. We also used several other measurements, such as flight distances and the number of mobbing calls directed at humans. The principal component analysis approach for OFT and MIS provided an activity-shyness axis and stress response axis in OFT and sociability-avoidance axis in MIS, which had significant repeatability within individuals. However, most axes were not significantly different between urban and rural areas, while the stress response of urban squirrels was significantly weaker than that of rural conspecifics. On the contrary, human-related behaviors such as flight distance and the number of mobbing calls toward humans were significantly different between urban and rural habitats. Therefore, behavioral modifications reported in previous studies might reflect only human-related disturbances: some urban animals such as mammals may be able to flexibly change behaviors depending on the situation, while their innate character or personality remains unchanged. This study underscores the importance of measuring multiple behaviors using different methods in non-avian species, focusing especially on human-associated behaviors.

Il Decreto CLIMA: nuove opportunità per le aree forestali ad elevato valore naturalistico

Abstract: The Decree on Climate 2019 represents an innovative and concrete framework for applying the international recommendations aimed at preventing and mitigating the effects of climate change. It focuses, in addition to many environment-related aspects, on the old-growth forests, recognizing them as forest ecosystems of high environmental value, defining their main ecological traits. According to this legislation, the extent of these forests in Italy is important, since many forest ecosystems have been left unmanaged from more than 60 years. Even if these stands are not always characterized by high level of naturalness, they are currently evolving towards more complex structures, due to the absence of human-related disturbance. Old-growth forests are unique ecosystems with a high structural complexity and peculiarities that are absent in managed forests. They are also an essential point of reference for sustainable forest management and environmental monitoring, in terms of conservation of biological diversity and ecological processes. For these reasons, they represent a unique benchmark for developing silvicultural models that incorporate knowledge of structural complexity (vertical and spatial) and developmental processes, duration of development and particularly the role of disturbances in creating structural legacies that become key elements of the post-disturbance stands. These forests, as the new Decrete underlines, must be protected, preserved and monitored in a long-term perspective, in order to safeguard their biodiversity, avoiding the structural simplification, which often characterizes the managed forests.

Adaptability of the threatened jaguarundi (Herpailurus yagouaroundi Schereber, 1777) to human-altered environments in San Luis Potosí, Mexico

Persistence and recovery of rare species in developing regions with limited protected areas depends upon their adaptability to human-altered habitats. The jaguarundi (Herpailurus yagouaroundi) is classed as threatened in Mexico, and knowledge of its distribution and environmental correlates is necessary for informed recovery efforts. However, little is known of jaguarundi habitat or distribution in interior Mexico, including the state of San Luis Potosí (SLP). We conducted 96 semi-structured interviews around communities, ejidos, and ranches throughout SLP to obtain records of jaguarundi presence and identify environmental correlates and site attributes associated with its occurrence. We evaluated interviews using analytical criteria of credibility, and collected habitat information from 50 reliable occurrences from three of the four geographic regions of SLP. Compared to the SLP landscape, jaguarundi occurrences were located closer to water, closer to roads, at lower elevation, marginally closer to communities, and in areas with greater total edge, edge density, and number of landscape patches. Jaguarundi showed preference for mosaics of tropical forest, agricultural, grassland, and urban (i.e., any community) cover types. Relatively dense hiding or ambush cover was usually present at occurrence sites. Collectively, maximum entropy modeling and logistic regression modeling predicted similar and high likelihood of jaguarundi presence in regions characterized by mosaics of tropical forest, agriculture, grassland, or urban cover types &lt;500 m in elevation and &lt;2 km from roads. These mosaic landscapes tended to be relatively close to communities of moderate population densities and water, and typically support higher small prey densities than less fragmented areas. Jaguarundi were adaptable to at least light–moderate human-related disturbance, and may be benefitted by it because of increased edge and habitat mosaics.

Combining multi-state species distribution models, mortality estimates, and landscape connectivity to model potential species distribution for endangered species in human dominated landscapes

Species ranges are changing in response to human-related disturbances and often management and conservation decisions must be based on incomplete information. In this context, species distribution models (SDMs) represent the most widely used tool, but they often lack any reference to demographic performance of the population under study, spatial structure of the habitat patches, or connectivity at the landscape level.Combining a multi-state SDM with a landscape pattern analysis and a mortality model, we developed a spatially-explicit, integrated model to assist and inform conservation planning for the Apennine brown bear in central Italy. We identified 15 critical habitat areas, potentially hosting 76 adult female bears. Many of these areas are, however, characterized by high levels of human-related mortality, making them attractive sink-like areas. Structural connectivity was higher in the northern part of the study area while only limited connectivity characterizes the core area, where most of the bears currently live.Our integrated model indicates that the conservation of this relict and isolated bear population is a realistic conservation goal, as we estimated that 192–270 bears could live across the Apennines. Our modelling framework enhances the biological realism of traditional SDMs and provides a conservation planning tool that integrates habitat suitability, mortality risk (as a component of the total demographic performance) and structural connectivity among habitat patches at the landscape scale. It is particularly suited for endangered species living in a human-modified landscapes where establishing a realistic and spatially explicit conservation goal would facilitate pro-active management.

Distribution patterns of east Australian humpback whales (Megaptera novaeangliae) in Hervey Bay, Queensland: a historical perspective

Tourism activities are expanding in both terrestrial and marine environments, which can have detrimental effects on the target species. Balancing the amount of disturbance a population of animals receives against the educational value of tourism requires localised research and adaptive management. This study examined the distribution of humpback whales within Hervey Bay, Queensland, using data spanning 2004–16, just before the implementation of a commercial ‘swim-with-whales’ program. Spatial and temporal patterns of humpback whale calves were of particular interest given that they are more vulnerable to human-related disturbances than other group types. We found that humpback whales displayed a distinct spatial segregation in Hervey Bay based on pod composition. Most whales displayed a residency time of two to three days, with females having a somewhat shorter residency time than males. These findings suggest that humpback whales in Hervey Bay not only display temporal segregation dependent on maturation and reproductive status, but fine-scale spatial distribution based on pod composition. Understanding habitat preference and patterns of habitat use of humpback whales in Hervey Bay is critical for effective management of the newly sanctioned swim-with-whale tourism in Hervey Bay and the sustained recovery of humpback whales in this region.