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Dispersal is an important process that is widely studied across species, and it can be influenced by intrinsic and extrinsic factors. Intrinsic factors commonly assessed include the sex and age of individuals, while landscape features are frequently-tested extrinsic factors. Here, we investigated the effects of both sex and landscape composition and configuration on genetic distances among bare-nosed wombats (Vombatus ursinus)—one of the largest fossorial mammals in the world and subject to habitat fragmentation, threats from disease, and human persecution including culling as an agricultural pest. We analyzed a data set comprising 74 Tasmanian individuals (30 males and 44 females), genotyped for 9,064 single-nucleotide polymorphisms. We tested for sex-biased dispersal and the influence of landscape features on genetic distances including land use, water, vegetation, elevation, and topographic ruggedness. We detected significant female-biased dispersal, which may be related to females donating burrows to their offspring due to the energetic cost of excavation, given their large body sizes. Land use, waterbodies, and elevation appeared to be significant landscape predictors of genetic distance. Land use potentially reflects land clearing and persecution over the last 200 years. If our findings based on a limited sample size are valid, retention and restoration of nonanthropogenic landscapes in which wombats can move and burrow may be important for gene flow and maintenance of genetic diversity. [ABSTRACT FROM AUTHOR]

Autotomy is the self-induced loss of a body part, which has evolved in animals at least nine times. Historically, autotomy has been seen as an anti-predator response that increases an animal's chances of escape and survival. However, autotomy can also provide benefits such as reducing the cost of injury, increasing reproductive success, and allowing escape from non-predatory entrapments. One group of animals that has a high occurrence of autotomy are decapod crustaceans, such as crayfishes, where up to 50% of individuals may have autotomized appendages. In the current study, we investigate the effect of claw autotomy on the digging behaviour in the Hillbilly Hairy Crayfish, Cambarus polypilosus. Our results demonstrate that there was no influence on digging regardless of whether one or two claws were autotomized. Further, we demonstrate that the claws of C. polypilosus are sexually monomorphic, which is unusual among crustaceans. [ABSTRACT FROM AUTHOR]

Burrow excavation by mammals generates heterogeneity within landscapes. Globally, these disturbances are known to provide significant ecosystem benefits. Most investigations of native Australian burrowing mammal disturbances has focused on the role of burrows in landscape function and interspecific thermal refugia. Herein, we present a novel observation of the fossorial skink Lerista bougainvillii utilizing burrow mounds of the common wombat (Vombatus ursinus) for possible thermoregulatory gains. In the early morning, when thermoregulatory opportunities were limited, L. bougainvillii were detected in mounds that appeared hotter than adjoining vegetation. These observations suggest that in densely vegetated habitats thermal heterogeneity caused by mammal burrows may offer important thermoregulatory opportunities for fossorial species with limited climbing capacity. [ABSTRACT FROM AUTHOR]

Subterranean rodents are often considered as ecosystem engineers because they physically modify the surrounding environment due to their burrowing and foraging activities. Understanding the modifications that ecosystem engineering species exert on the environment are of crucial importance in ecology studies, since they may affect the structure and population dynamics of several species, including lizards. Thus, the objective of the present study is to test the effect that Ctenomys mendocinus exert in the abundance of Liolaemus ruibali and its escape behaviour, in a high‐elevation desert. Lizard abundance was estimated using observation transects and escape behaviour was studied with an experiment where the observer was considered by lizards as a potential predator and distance before the lizard flees was measured. All the variables were compared between areas disturbed by C. mendocinus and undisturbed ones. We found that L. ruibali was favoured by C. mendocinus activity. By creating burrow systems that serve as refuges for lizards, this rodent species increases the abundance of L. ruibali and reduces its flight distance, thereby improving its escape performance. We may suggest that C. mendocinus, through the construction of burrow systems, would be acting as an ecosystem engineer in Puna desert, affecting L. ruibali ecology. [ABSTRACT FROM AUTHOR]

Earthworms have a prominent role in supporting soil functioning and thus in providing key services to humanity. Their beneficial role relates to effects on soil structure, carbon and nutrient cycling as well as the soil microbial community. Optimizing the role of earthworms in agricultural systems is therefore crucial for maintaining or improving soil quality and supporting a more sustainable, circular agriculture. Here, we summarize established knowledge on the role of earthworms in agronomy; present novel insights from the past decades; and identify key knowledge gaps to be addressed in the future to fully benefit from earthworms in our agricultural soils. We start by discussing how earthworms affect basic soil processes through their effects on soil structure, microbial communities and biogeochemical cycles. Further, we show how as a result of these changes, earthworms indirectly affect plant growth, the soil greenhouse gas balance and play a role in remediation of contaminated arable soils. We further address one of the paradoxes of earthworm ecology: that they are often not present in the soils where they are most needed. We subsequently discuss potential solutions to this paradox. Finally, we identify 10 key questions that need to be addressed in the near future. In our view, recognizing that earthworms are not a stand-alone solution to improving the sustainability of cropping systems, but an essential piece of the puzzle is crucial for optimizing the benefits they offer in agronomic systems. By managing our earthworm populations well, we manage our soils well. [ABSTRACT FROM AUTHOR]

Background: Zoonotic cutaneous leishmaniasis is a major public health problem in Iran with the main vector of Phlebotomus papatasi. The use of entomopathogenic fungi for biological control of the vector is a potential substitute for the current methods which are being used. The purpose of the current study was to assess the virulence of two local isolates of Beauveria bassiana (OZ2 and TV) against Ph. papatasi. Methods: To perform the bioassay test, fungal suspensions were applied for every stage of the sand fly life cycle. The mortality rate, longevity, and number of eggs laid were determined. Also, the probability of fungal survival on the surface of rodent’s body was assessed. Results: The longevity of infected adult sand flies with both isolates of B. bassiana was significantly lower (P< 0.05) in comparison to the negative control. The estimated Lethal concentration 50 (LC50) values for adult female and male sand flies treated with OZ2 isolate were 1.4×106 and 2.2×107 conidia/ml, respectively, while they were 6.8×106 and 2.3×108 conidia/ml for TV isolate, respectively. Both isolates of B. bassiana exhibited nonsignificant mortality rates in sand fly larvae and pupae and fecundity rate (P> 0.05). According to our findings for both isolates, the fungus continued to spread throughout the surface of the rodent's body for 144 hours after spraying. Conclusion: The current study demonstrated that both isolates of B. bassiana have considerable biological control capacity against adult sand flies. [ABSTRACT FROM AUTHOR]

Understanding adaptations to extreme weather events by endangered species is critical to inform conservation decisions, particularly when their adaptations relate to artificial habitat supplementation at translocation sites. Apnoea, temporary suspension of breathing, has been observed as an anti‐predator adaptation by semi‐aquatic reptiles that dive underwater for periods of time to avoid detection. This study reports on the observations of an endangered grassland skink, the pygmy bluetongue (Tiliqua adelaidensis), remaining submerged in rain‐induced flooded artificial burrows at an experimental translocation site. [ABSTRACT FROM AUTHOR]

Increased predation where ground cover is reduced after severe wildfire is increasingly implicated as a factor causing decline of vulnerable prey populations. In arid central Australia, one species detrimentally affected by repeated wildfire is the great desert skink or tjakura (Liopholis kintorei), a distinctive lizard of the central Australian arid zone that constructs and inhabits multi‐entranced communal burrows. We aimed to test whether tjakura or predator activity at burrow entrances varied with cover and how tjakura respond to predator presence. Using time‐lapse photography, we monitored tjakura and predator activity at the largest entrance of 12 burrows ranging from high (>70%) to low (<50%) cover and at multiple entrances of two other burrows. Overall activity did not vary between burrows with high and low cover. Within burrow systems tjakura were more active at sparsely vegetated entrances, often sitting wholly or partly inside the burrow. However, consistent between and within burrow systems, skinks spent proportionally more time fully outside where cover was higher. Predators—mostly native—were detected at most burrows, with no apparent relationship between predator activity and cover. Skinks also did not appear to modify their activity in response to predator visits. Our results indicate that tjakura may spend more time outside burrow entrances when cover is higher but there was no direct evidence that this related to perceived or real predation risk. Differences in food availability, thermoregulatory opportunities and opportunities for ambush foraging associated with differences in vegetation cover or composition are other factors likely to be important in determining the activity of tjakura at burrows. Our research demonstrates the usefulness of camera traps for behavioural studies of ectothermic burrowing animals. The complex relationships between tjakura activity and vegetation cover thereby revealed, suggest outcomes of fire‐mediated habitat change on predator–prey interactions are not easily predictable. [ABSTRACT FROM AUTHOR]

Ecosystem engineers influence the physical environment, which changes the distribution and availability of resources to other organisms. Based on their burrowing abilities, freshwater crayfish have been widely recognised as ecosystem engineers. Crayfishes construct burrows that range from simple, rudimentary depressions in aquatic systems, to complex, labyrinth-like terrestrial burrows that may be significant distances from permanent water bodies. Here, we investigate ecosystem engineering and burrowing of the slender crayfish, Faxonius compressus, which lives in lotic environments characterised by an abundance of small cobble- and gravel-sized substrates. Without larger substrates to burrow under, we found F. compressus populations construct extremely high densities of burrows across riffle, run and pool macrohabitats. Based on the average number of burrows, a 5 × 100 m pool is estimated to contain an average of 25,860 burrows. We also conducted behavioural observations of this species to glean information on their natural history. Faxonius compressus regularly inhabits and competes for ownership of burrows which serve as a shelter from predators. Importantly, these burrows are not only used by F. compressus; we documented other crayfishes and fish species utilising these burrows. In total, we documented two other crayfishes and six fish species utilising F. compressus burrows. We discuss the ecosystem engineering abilities of this species in relation to other crayfish and suggest future avenues of research to elucidate this species' natural and life history. [ABSTRACT FROM AUTHOR]

Burrowing mammals strongly impact plant communities. One of the main effects is accelerating nutrient cycling and thus promoting plant growth. This mechanism is well‐studied in grasslands and alpine habitats, but less is known about this phenomenon in arid, cold mountain environments. We studied ecosystem engineering by long‐tailed marmots (Marmota caudata) by measuring the content of plant nitrogen and phosphorus, as well as nitrogen stable isotopes in plant biomass and marmot feces in a distance gradient up to 20 m from marmot burrows in an extremely arid glacier valley in Eastern Pamir, Tajikistan. We also captured aerial images of the area inhabited by marmots to study the spatial distribution of vegetation. There was a weak relationship between the presence of burrows and vegetation cover on soil not covered by burrow material. Burrow mounds were not colonized by plants, as opposed to other studies, where mounds are often microhabitats that enhance plant diversity. A significant increase in N and P in aboveground green plant biomass in the proximity of burrows was found in one out of six studied plant species. Contrary to our expectations, stable N isotopes did not give further insight into N routing. We assume that plant growth is strongly limited by water availability, which prevents them from utilizing the local increase in nutrients, certainly provided by marmot activity. The results are contrary to numerous studies, which showed that the role of burrowing animals as ecosystem engineers increases with increasing abiotic stress, including aridity. This shows a lack of this type of study at the end of the gradient of abiotic factors. The presence of marmots and their burrows has surprisingly little effect on plant nutrient content and on vegetation cover in an extremely arid, cold mountain habitat. Burrow mounds are no microhabitats, as there is no plant succession on them. The results are contrary to previous studies on the effect size of ecosystem engineering in arid environments. [ABSTRACT FROM AUTHOR]

A native Australian corvid, Little Raven Corvus mellori, has emerged as a dominant and problematic predator of an ecologically and economically important seabird, the Little Penguin Eudyptula minor. In 2013, ravens successfully preyed upon clutches/broods of the burrow-nesting penguin, especially those in shallower, more accessible burrows. Individual raven size might mediate which ravens attack penguins; smaller ravens may be able to enter burrows more easily; alternatively, larger ravens may be more capable of overcoming penguin parental defence. Here, we consider the predator-prey interactions to assess whether associations with burrow characteristics persisted and examine whether raven size mediated propensity to prey upon penguin eggs. We compared data from the 2013 and 2015 penguin breeding seasons at Phillip Island (Victoria, Australia) for differences in clutch survival and burrow characteristics. We also examined raven morphometrics to determine if any physical differences existed between known burrow-predators (“culprits”) and other birds. During the 2013 breeding season, penguins suffered clutch losses of 61.1% compared with 33.9% in 2015. Burrow characteristics changed between seasons—most noticeably, burrows were deeper in 2015 and ravens no longer discriminated between burrow characteristics. Culprits were heavier and larger. While we could not eliminate inter-annual variability as a possible contributing factor, our results were consistent with rapid adaptation of prey and predator to intense emergent depredation. Penguins may now construct deeper burrows, and ravens evidently no longer select more vulnerable burrows. Larger ravens may be more capable of approaching and attacking penguin burrows. [ABSTRACT FROM AUTHOR]

Larvae of the burrowing polymitarcyid mayfly Tortopus circumfluus are recognized for the first time and positively identified as the excavators of simple U– and pouch–shaped, inclined to vertical, burrows in well–consolidated, firmground clay, silt, and sand cutbanks of the Colorado River in Columbus, Texas, USA. Hydro–stone casts of these burrows reveal architectural details that facilitate comparison to other reported modern mayfly burrows as well as ichnofossils attributed to Ephemeroptera. Polymitarcyid burrows from rivers in Poland and the Czech Republic resemble those excavated by T. circumfluus but are larger with a more regular pattern of bioglyphs. Glossifungites gingrasi from Turonian fluvial deposits of central Utah, USA, is architecturally similar to T. circumfluus burrows, although G. gingrasi are larger and nearly horizontally inclined. The large ephemerid mayfly Hexagenia limbata is sympatric with T. circumfluus in the Colorado River and constructs sinuous U–, J–, and S–shaped burrows in poorly consolidated, softground deposits in deeper sections of the channel thalweg. If encountered in the rock record, H. limbata burrows might be referred to Arenicolites variabilis. Detailed investigations of extant mayfly burrows while thus far rare, can inform not only interpretations of the rock record, but also conservation assessments for imperiled taxa. [ABSTRACT FROM AUTHOR]

Burrowing species rely on subterranean and subnivean sites to fulfill important life-history and behavioral processes, including predator avoidance, thermoregulation, resting, and reproduction. For these species, burrow architecture can affect the quality and success of such processes, since characteristics like tunnel width and chamber depth influence access by predators, thermal insulation, and energy spent digging. Wolverines (Gulo gulo) living in Arctic tundra environments dig burrows in snow during winter for resting sites and reproductive dens, but there are few published descriptions of such burrows. We visited 114 resting burrows and describe associated architectural characteristics and non-snow structure. Additionally, we describe characteristics of 15 reproductive den sites that we visited during winter and summer. Although many resting burrows were solely excavated in snow, most incorporated terrain structures including cliffs, talus, river shelf ice, thermokarst caves, and stream cutbanks. Burrows typically consisted of a single tunnel leading to a single chamber, though some burrows had multiple entrances, branching tunnels, or both. Tunnels in resting burrows were shorter than those in reproductive dens, and resting chambers were typically located at the deepest part of the burrow. Reproductive dens were associated with snowdriftforming terrain features such as streambeds, cutbanks on lake edges, thermokarst caves, and boulders. Understanding such characteristics of Arctic wolverine resting and reproductive structures is critical for assessing anthropogenic impacts as snowpack undergoes climate-driven shifts. [ABSTRACT FROM AUTHOR]

Animals often adjust their behavior according to social context, but the capacity for such behavioral flexibility can vary among species. Here, we test for interspecific variation in behavioral flexibility by comparing burrowing behavior across three species of deer mice (genus Peromyscus) with divergent social systems, ranging from promiscuous (Peromyscus leucopus and Peromyscus maniculatus) to monogamous (Peromyscus polionotus). First, we compared the burrows built by individual mice to those built by pairs of mice in all three species. Although burrow length did not differ in P. leucopus or P. maniculatus, we found that P. polionotus pairs cooperatively constructed burrows that were nearly twice as long as those built by individuals and that opposite‐sex pairs dug longer burrows than same‐sex pairs. Second, to directly observe cooperative digging behavior in P. polionotus, we designed a burrowing assay in which we could video‐record active digging in narrow, transparent enclosures. Using this novel assay, we found, unexpectedly, that neither males nor females spent more time digging with an opposite‐sex partner. Rather, we demonstrate that opposite‐sex pairs are more socially cohesive and thus more efficient digging partners than same‐sex pairs. Together, our study demonstrates how social context can modulate innate behavior and offers insight into how differences in behavioral flexibility may evolve among closely related species. [ABSTRACT FROM AUTHOR]

The question of the heritability of behavior has been of long fascination to scientists and the broader public. It is now widely accepted that most behavioral variation has a genetic component, although the degree of genetic influence differs widely across behaviors. Starting with Mendel’s remarkable discovery of “inheritance factors,” it has become increasingly clear that specific genetic variants that influence behavior can be identified. This goal is not without its challenges: Unlike pea morphology, most natural behavioral variation has a complex genetic architecture. However, we can now apply powerful genome-wide approaches to connect variation in DNA to variation in behavior as well as analyses of behaviorally related variation in brain gene expression, which together have provided insights into both the genetic mechanisms underlying behavior and the dynamic relationship between genes and behavior, respectively, in a wide range of species and for a diversity of behaviors. Here, we focus on two systems to illustrate both of these approaches: the genetic basis of burrowing in deer mice and transcriptomic analyses of division of labor in honey bees. Finally, we discuss the troubled relationship between the field of behavioral genetics and eugenics, which reminds us that we must be cautious about how we discuss and contextualize the connections between genes and behavior, especially in humans. [ABSTRACT FROM AUTHOR]

This study shows how beaver digging activity can affect water body morphology and local biota under modern environmental conditions in a small floodplain lake. The total area of microhabitats created by beavers was found to reach 7% of water body area and 30% of littoral-zone area. It was noted that the zoogenic microhabitats are different when depth is greater and plant cover is smaller, especially of emergent vegetation. Helophytes Sparganium erectum and Alopecurus aequalis were found to prefer the beaver-unaffected part of the littoral. Invertebrates Naucoris sp. and Hydrophilus sp. prefer beaver microhabitats, whereas Planorbis planorbis, Lymnaea palustris, and Hydrous sp. prefer thickets of emergent plants in beaver-unaffected littoral areas. Adult crucian carps Carassius carassius proved to be abundant in the beaver-unaffected part of the water body, while the adult weatherfish Misgurnus fossilis prefers beaver burrows, and its fry inhabit beaver-unaffected sites. A similar situation was observed for marsh frogs Pelophylax ridibundus: adults prefer beaver microhabitats in June, but frog tadpoles mainly inhabit a beaver-unaffected littoral. Tadpoles of Pelobates vespertinus proved to be slightly aggregated near beaver burrows in July. The beaver activity was found to slightly increase β-diversity within the water body according to Jaccard indices. The results confirm that the beaver-created heterogeneity is important for aquatic biota under conditions of shallowing of floodplain water bodies. This study shows how beaver digging activity can affect water body morphology and local biota under modern environmental conditions in a small floodplain lake. The results confirm that the beaver-created heterogeneity is important for aquatic biota under conditions of shallowing of floodplain water bodies. [ABSTRACT FROM AUTHOR]

Abstract: Many analgesics inadequately address the psychiatric comorbidities of chronic and persistent pain, but there is no standard preclinical model of pain-altered behavior to support the development of new therapies. To explore this conflicting and inconclusive literature, we conducted a focused systematic review and meta-analysis on the effect of complete Freund adjuvant-induced (CFA) rodent hind paw inflammation on multiple classical indicators of exploratory behavior, stress coping, and naturalistic behavior. Our primary objective was to define CFA's effect on assays including, but not limited to, the elevated plus maze and forced swim test. Our secondary objective was to discover how variables such as species and strain may influence outcomes in such assays. We searched Ovid MEDLINE, Embase, Scopus, and Web of Science in April and October 2020 for studies with adult rodents injected with CFA into the hind paw and subsequently tested for aspects of "anxiety-like" or "depressive-like" behaviors. Forty-four studies evaluated performance in the elevated plus or zero maze, open field test, light-dark box, place escape and avoidance paradigm, forced swim test, tail suspension test, sucrose preference test, wheel running, and burrowing assay. Complete Freund adjuvant modestly but significantly decreased exploratory behavior, significantly increased passive stress coping in the tail suspension test but not the forced swim test, and significantly decreased preference for sucrose and naturally rewarding activity. Subgroup analyses revealed significant differences between species and animal sourcing. Based on the evidence provided here, we conclude future studies should focus on CFA's effect on natural rewards and naturalistic behaviors. [ABSTRACT FROM AUTHOR]

The objectives were to characterize the habitat of the burrowing owl (Athene cunicularia hypugaea) and to know the variables related to the presence of the species in Coahuila, Durango, San Luis Potosi and Zacatecas, Mexico. The search for the owl took place from May to October 2018. The localized burrows were geo-referenced and measured. The sites with burrows were characterized, in plots of 20x20 m, from September to December 2018, taking as center the burrows, was measured: slope, aspect, cover of the soil, density of plants, among others. To identify any possible habitat selection by this species; for each active burrow, two randomly established plots were evaluated. The sites with presence were: three in Coahuila, one in Durango, four in San Luis Potosí and two in Zacatecas. Based on the results of the Poisson regression analysis, the variables associated with the burrows were: A) height of the burrow entrance, b) height of the burrow mound, c) width of the entry, d) cover of grasslands and e) woody material. The information generated in this study can be used to complement a management plan for the conservation of the species in central-northern Mexico. [ABSTRACT FROM AUTHOR]

The trace fossil Thalassinoides includes ichnospecies that have been recognised for a long time and widely used in the interpretation of depositional systems. Despite its broad occurrence, the ichnotaxonomic status of this important ichnogenus is far from being unmistakable, which in turn hampers its application in palaeoenvironmental reconstructions. One of the most common ichnospecies is Thalassinoides paradoxicus , originally described from the Paradoxica Bed of the Lower Chalk in the Hunstanton Cliff in SE England. To demarcate this characteristic form from similar ichnospecies, T. paradoxicus is reexamined and described from its type locality. It is characterised by an 'irregular, very extensive horizontal burrow network, occurring at several levels, connected by vertical shafts' (Kennedy), but its morphological variability also includes a range of significant architectural elements as well as burrow portions with a laminated wall, scratches and pellets. A series of colonisation events along omission surfaces can be reconstructed based on the occurrence of several burrow generations. T. paradoxicus is an important constituent of shallow-marine environments and subtle variations in morphology may help to constrain facies interpretations. Based on modern analogues and finds of body fossils within their burrows, decapod crustaceans (foremost callianassid shrimp) are known producers of T. paradoxicus from the Mesozoic onwards, whereas older records can be attributed to other malacostracans but also trilobites. • Detailed description of the trace fossil Thalassinoides paradoxicus from its type locality. • Taxonomic distinction from similar ichnotaxa. • Interpretation as shrimp burrows. • Common in shallow-marine environments with omission and erosion surfaces. [ABSTRACT FROM AUTHOR]

The three main ecological categories of earthworms (anecic, endogeic, epigeic) are often used as proxies for functional groups. This is troublesome since they were not designed for this purpose and thus the relevance of such a use was never tested nor proven. How earthworms influence the different soil functions is tightly linked to their bioturbating behavior and thus they are considered as physical ecosystem engineers. Here, we characterized the different facets of this behavior (burrow creation, production of casts below and above ground, and litter consumption) for 50 species or subspecies of European earthworms under standardized laboratory conditions. Using PCA and K-means methods, we defined six new functional groups of earthworms, i.e. intense tunnelers, burrowers, shallow bioturbators, deep bioturbators, litter dwellers and intermediates. Intense tunnelers and burrowers build continuous and vertically oriented burrows, the first however burrow more and consume less litter. Deep bioturbators live deeply in the soil, make very discontinuous burrows and consume no litter. They could be seen as a novel group but they can be linked to the hypo-endogeics ecological categories defined 50 years ago. Litter-dwellers and shallow bioturbators can be respectively linked to the epidegeics and endogeics ecological categories. However, the new groups only partially overlap with the traditional ecological categories. We assume that their use, based on quantitative behavioral assessments, will improve the study of the relationships between earthworm communities and the associated provision of ecosystem services by minimizing the overlooked variability within the three main ecological categories regarding their behavior. [Display omitted] • Earthworm ecological categories are not functional groups. • We measured the bioturbating behaviour of 50 earthworm taxa under standardized conditions. • We defined 6 functional groups that only partially overlap with ecological categories. • Deep bioturbator earthworms were rediscovered as a functional group. [ABSTRACT FROM AUTHOR]

Pangolins in the genus Manis are nocturnal, burrowing, insectivorous mammals listed as Critically Endangered or Endangered by the International Union for Conservation of Nature. Two species of pangolins are found in Nepal: the Chinese pangolin (Manis pentadactyla) and Indian pangolin (Manis crassicaudata). Despite having high conservation priority, little attention has been given to conservation interventions of both species of pangolins found in the Terai region (low land) of Nepal. The present study assesses habitat use and factors affecting the habitat choice of pangolins in low land (Terai), Nepal, focusing on Amritdharapani Community Forest of Chitwan district. Pangolin burrows were used as the indirect signs, and opportunistic sampling method was used to record the burrows. After the identification of all occurrence sites (burrows) in the field, random points were generated excluding the points where burrows were recorded for sampling of nonoccurrence sites. A total of thirty‐nine burrows were observed at elevations ranging from 301 to 413 masl. Burrows were frequently associated with northwest aspects, gentle slope (15°–20°), moderate canopy cover (51%–75%), red‐colored soil, and acidic soils with pH 6.5–7. The burrows were most common in areas with weak human disturbance (i.e., 1,500–1,700 m from settlements), 800–1,200 m from roads, and within 300 m from a water source and within 20 m from the nearest termitarium. Distance to settlement, distance to road, soil pH, and canopy cover were found to affect the habitat choice of pangolins in the study area. [ABSTRACT FROM AUTHOR]

Scientists collect fleas (Siphonaptera) to survey for Yersinia pestis, the bacterial agent of plague. When studying fleas parasitizing prairie dogs (Cynomys spp.), two primary methods are used: (1) combing fleas from live-trapped prairie dogs and (2) swabbing fleas from burrows with cloth swabs attached to metal cables. Ideally, burrow swabbing, the cheaper and easier method, would explain flea burdens on prairie dogs and provide reliable information on plague prevalence. In a linear regression analysis of data from 1-month intervals (June–August 2010–2011) on 13 colonies of black-tailed prairie dogs (Cynomys ludovicianus, BTPDs) in New Mexico, flea abundance on swabs explained 0–26% of variation in BTPD flea burdens. In an analysis of data (May–August 2016) from six colonies of BTPDs in Montana, flea abundance on swabs explained 2% of variation in BTPD flea burdens. In an analysis of data from a short-term interval (July 23–27, 2019) on four colonies of BTPDs in Montana, flea abundance on swabs explained 0.1% of variation in BTPD flea burdens. In an analysis of data from 1-week intervals (August–October 2000) on four colonies of white-tailed prairie dogs (Cynomys leucurus, WTPD) in Utah, swabbing data explained 0.1% of variation in WTPD flea burdens. Pools of fleas from two WTPD colonies were tested for Y. pestis by mouse inoculation and isolation; 65% from WTPDs tested positive, whereas 4% from burrows tested positive. Data herein also show that results from burrow swabbing can misrepresent flea species composition and phenology on prairie dogs. Burrow swabbing is useful for some purposes, but limitations should be acknowledged, and accumulated data should be interpreted with caution. [ABSTRACT FROM AUTHOR]

Nesting in burrows is uncommon among birds, but one example of a burrow-nesting raptor is the Burrowing Owl (Athene cunicularia). In most areas of North America, where this raptor has been extensively studied, it typically uses burrows of fossorial mammals, but in southern South America this owl digs its own burrows. We studied characteristics of size, lining, and decoration of Burrowing Owl nests located in dunes, rural areas, and urban areas of the Pampas of Argentina, and analyzed whether such characteristics vary according to land cover. We found that Burrowing Owls construct burrows of similar characteristics in the three habitats sampled, although nests in dunes had wider entrances and longer tunnels. Such variation might relate to the soil, which is more compacted in the dunes than at the rural and urban areas. In both rural and urban areas, owls used manure to line the burrow and decorated the nest entrance with visible objects, but the diversity and amount of materials used for decoration was much higher in urban nests. Our results on burrow measurements, burrow-lining, and decoration behavior of Burrowing Owls in the Pampas were consistent with those reported for North American populations, even though burrow construction processes differ at both ranges of the species' distribution. [ABSTRACT FROM AUTHOR]

Across the Midwestern United States, farmers have increasingly used winter cover crops in corn–soybean rotations to improve soil health. Although this practice has many benefits, it also can provide habitat for potential pest species, such as voles (Microtus pennsylvanicus and M. ochrogaster). Voles have been reported by farmers to damage soybean plants in fields which had recently been cover cropped, but little has been done to quantify levels of damage related to their abundance. We evaluated the relationship between vole sign and soybean plant damage to help farmers manage this unintended consequence of using cover crops. We counted the frequency of vole sign along transects in cover‐cropped fields. In addition to vole sign, we considered influence of cover‐crop density, distance to field edge, and presence of artificial raptor perches when fitting negative binomial generalised linear mixed models to predict amount of soybean plant damage. An additive model including all explanatory variables and factors best explained variation in vole damage. Number of burrow entrances, presence of raptor perches, and cover‐crop density were positively associated with soybean plant damage. Burrow entrances were most strongly associated with damage. Farmers can use frequency of burrow entrances to predict relative amounts of damage likely to be incurred; conditions in a field should be considered when deciding to manage for reduced vole populations before planting soybeans. [ABSTRACT FROM AUTHOR]

Constructing burrows is energetically expensive, yet is a common trait across a broad spectrum of animals. The benefits of using burrows must therefore outweigh the costs of constructing burrows, which may reduce the risk of predation and/or ease the need for active thermoregulation. We examined the use of burrows in Butterfly Lizards (Leiolepis belliana), a common Southeast Asian lizard that constructs burrows in open, sandy plains. We used radiotelemetry to track the activity patterns and measured the thermal environment of 12 individuals across 14 d of sampling. We found that L. belliana had high site fidelity, using the same burrows across the sampling period. There were significant differences between substrate temperatures inside and outside the burrow across the whole sampling period. However, the lower internal burrow temperature still exceeded the upper thermal tolerance of a similar sized lizard species during midday, and this probably explains why we did not observe lizards in their burrows during the middle of the day. Burrows were constructed in a shallow, Y-shaped, concave shape, with each of the three branches of the Y ending in a surface opening, a design that allows for easy escape if threatened by a predator. Due to burrow temperatures exceeding lethal body temperatures for much of the day, and the Y-shape structure of the burrows, we propose that the major function of burrows for this species is as a predator escape mechanism. [ABSTRACT FROM AUTHOR]

Litter decomposition in most terrestrial ecosystems is regulated by moisture-dependent microorganism activity, among other things. Decomposition models typically underestimate rates of plant litter decomposition in drylands, suggesting the existence of additional drivers of decomposition. Attempts to reveal these drivers have predominantly focused on abiotic degradation agents, alternative moisture sources, and soil–litter mixing. The role of burrowing animals in promoting decomposition has received less attention despite greatly contributing to plant litter transfer from the harsh desert surface to the moister and nutrient-rich environment belowground. Our goal was to explore how macro-detritivore burrows affect plant litter mineralization dynamics. We introduced 13C-labeled litter belowground into (1) desert isopod (Hemilepistus reaumuri) burrows and (2) artificial burrows, and aboveground on top of (3) isopod fecal pellet mounds and (4) bare soil crust. We compared the litter mass loss between the four treatments and used cavity ring-down spectroscopy to reveal the in situ mineralization dynamics. No litter mineralization was evident during the dry summer months both above- and belowground. Following rain events, mineralization rates spiked in all four micro-environments, quickly diminishing aboveground while slowly waning belowground. Total litter mass loss was twofold higher below than aboveground and was significantly higher in isopod burrows compared to artificial burrows. Our findings demonstrate that burrowing macro-detritivores promote litter decomposition in deserts by transferring organic matter to their burrows where favorable climatic conditions and a nutrient-enriched environment foster microbial activity. Thus, attempts to resolve the dryland decomposition conundrum should not be limited to exploring factors that allow decomposition under harsh desert surface climatic conditions, but focus on the role that animals play in facilitating decomposer-friendly environments to which they translocate plant litter. [ABSTRACT FROM AUTHOR]

The white-toothed woodrat (Neotoma leucodon) inhabits the arid zones of north-central Mexico and it is important for rural communities for food and economic income. The objective was to characterize the habitat of the white-toothed woodrat in the Potosino-Zacatecano Plateau. In 44 sites with burrows and 44 random sites, the altitude, slope, slope exposure, ground cover: shrubs, grasses, rock, woody material and bare soil, as well as the density of prickly pear cactus, agave, shrubs and palms were recorded. In addition, 21 hunter-gatherers (H-G) were surveyed about woodrat habitat conditions. The woodrat builds its burrows in agaves (40.4 %) and 47.6 % of the H-Gs stated that the woodrat was more frequent in prickly pear cactus. Ninety % of the burrows were located on terrain with low slopes (= 4 %), where shrub density and cover were dominant (2085.6 ± 1825 ha -1, 36.1 ± 17.5%, respectively). Rat burrows are associated with shrubs and cactus, as they provide them with food and protection from predators. The H-G consider that in order to conserve the woodrat it is necessary to allow them to reproduce, establish hunting seasons and maintain the vegetation. [ABSTRACT FROM AUTHOR]

The European eel (Anguilla anguilla) is a fascinating species, exhibiting a complex life cycle. The species is, however, listed as critically endangered on the IUCN Red List due to an amalgam of factors, including habitat loss. This study investigated the burrowing behaviour and substrate preference of glass, elver and yellow stages of A. anguilla. Preference was determined by introducing eels in aquaria with different substrates and evaluating the chosen substrate for burrowing. In addition, burrowing was recorded using a camera in all substrate types and analysed for kinematics. The experiments showed that all of these life stages sought refuge in the sediments with particle sizes ranging from sand to coarse gravel. Starting from a resting position, they shook their head horizontally in combination with rapid body undulations until half of their body was within the substrate. High‐speed X‐ray videography revealed that once partly in the sediment, eels used only horizontal head sweeps to penetrate further, without the use of their tail. Of the substrates tested, burrowing performance was highest in fine gravel (diameter 1–2 mm; lower burrowing duration, less body movements and/or lower frequency of movements), and all eels readily selected this substrate for burrowing. However, glass eels and elvers were able to use coarse gravel (diameter >8 mm) because their smaller size allowed manoeuvring through the spaces between the grains. Further, burrowing performance increased with body size: glass eels required more body undulations compared to yellow eels. Interestingly, the urge to hide within the sediment was highest for glass eels and elvers. Documentation of substrate preference and burrowing behaviour of A. anguilla provides new information about their potential habitat use. Considering that habitat alterations and deteriorations are partly responsible for the decline of the eel, this information can contribute to the development of more effective conservation measures. [ABSTRACT FROM AUTHOR]

is a small-bodied ornithischian dinosaur from the mid-Cretaceous Blackleaf and Wayan Formations of Montana and Idaho, respectively, and is the only documented dinosaur with evidence of a burrowing ecology. The type locality, from the Blackleaf Formation of southwestern Montana, consisted of an infilled burrow structure containing the disarticulated skeletons of one adult and two juveniles and represents a rare association of body fossils and trace fossils of a single dinosaur taxon. While these fossils and their paleobiological implications were unprecedented, collection nevertheless necessitated removal of the burrow structure from its geological context and its destruction during body fossil preparation. Here we present the first photogrammetric models of the type locality burrow in its original geological context and three dimensional morphology, constructed from photos taken at three stages in excavation. Because the terminal extent of the burrow was collected prior to the burrow's complete exposure, the structure was never documented in its entirety. A composite model provides the only holistic documentation of the entire burrow morphology as originally preserved. These models supplement the original burrow description, serve as comparative tools for identifying and diagnosing future discoveries, and demonstrate the utility of pre-existing photographs for later photogrammetric reconstruction. [ABSTRACT FROM AUTHOR]

Burrows produced by marine invertebrates often harbor other small commensal invertebrates. The mud shrimp Upogebia is known to coexist with the myid bivalve Cryptomya in a burrow produced by the shrimp. Both species are filter-feeders, and thus interspecific competition or trophic niche segregation may occur in the burrow. Samples for carbon and nitrogen stable isotope analysis were collected from a tidal flat near the tidal inlet of Akkeshi Lake, Hokkaido, northern Japan in April 2013. In addition, stratified benthos sampling was conducted on the tidal flat in August 2018, to clarify the interspecific relationship between U. major and C. busoensis in the burrow. The stratified benthos sampling showed the vertical distribution of these species, and indicated that both species filter water from the same part of the burrow for feeding. The stable carbon and nitrogen isotope analysis showed that important food sources for both U. major and C. busoensis are marine phytoplankton and microphytobenthos. In addition, C. busoensis is likely to consume terrestrial organic matter whereas U. major is unable to utilize it. The partial trophic segregation between the species increases the potential benthic filtering because it allows the Upogebia burrow complex to consume a wide variety of organic matter, and it might reduce interspecific competition between the filter-feeding host and its commensal species. These results demonstrate how ecologically similar macrobenthos can coexist in a burrow. [ABSTRACT FROM AUTHOR]

Burrow‐digging organisms act as ecosystem engineers, providing potential habitat to other organisms. In the Mid North region of South Australia, wolf and trapdoor spiders in fragmented grassland communities provide this service. Pygmy bluetongue lizards are an endangered skink, endemic to these grasslands. The lizards obligatorily use burrows dug by these spider groups as refuges, basking sites and ambush points. We investigated the occupancy of these spider burrows by lizards and other organisms within the grassland community, identifying the occasions that burrows were shared by multiple taxa. We found that the lizards and trapdoor spiders are predominantly solitary, while wolf spiders co‐shared burrows more frequently with either weevils or snails. There were numerous taxa that were found to regularly co‐share with other taxa, particularly snails, centipedes and weevils. There was a strong temporal influence on burrow sharing, with most co‐sharing occurring late in summer. This study provides an insight into the use of burrows by the lizards and co‐existing taxa within these grassland communities. The dynamics of burrow‐use by other taxa have the potential to influence long‐term conservation of these lizards as burrow availability is crucial to their survival in these grasslands. [ABSTRACT FROM AUTHOR]

The great desert skink (Liopholis kintorei) of the Egerniinae subfamily (Reptilia: Scincidae) is a communal burrowing lizard that inhabits arid spinifex grasslands in central Australia. Great desert skink activity is centred in and around the burrows which are inhabited for many years. However, it is not known whether skinks select burrow sites with specific attributes or how continuing occupancy of burrows is influenced by the surrounding habitat; especially post‐fire, when plant cover is reduced. Here, we test whether great desert skink burrows in areas burnt 2 years previously and in longer unburnt areas are associated with particular habitat attributes, and whether there are differences between occupied and recently abandoned burrow sites. Vegetation composition, cover and soil surface characteristics at 56 established great desert skink burrows, including occupied and recently unoccupied burrows, were compared with 56 random nearby non‐burrow control sites. Burrow sites had higher plant cover compared with the surrounding landscape in both recently burnt and longer unburnt areas and were more likely to be associated with the presence of shrubs. Soil stability and infiltration were also higher at burrow sites. However, we found no evidence that burrows with lower cover were more likely to be abandoned. Our results suggest that great desert skinks may actively select high cover areas for burrow construction, although differences between burrow and control sites may also partly reflect local changes to plant cover and composition and soil properties resulting from burrow construction and long‐term habitation of a site. Further research should determine if burrows with shrubs or higher plant cover provide greater protection from predators, more structural stability for burrow construction, increased prey abundance or other benefits. We recommend that maintenance of areas with relatively higher plant cover be prioritized when managing great desert skink habitat. [ABSTRACT FROM AUTHOR]

Fiddler crabs are abundant, semi-terrestrial crustaceans inhabiting tropical, subtropical and warm temperate coasts worldwide. Some species build above-ground sedimentary structures at or near the opening to their burrows. The functions and shapes of these constructions vary interspecifically and according to the sex of the builder. Here, we compile the dispersed reports on these structures, suggest uniform naming for different shapes, review explanations for their functions and explore associations between the attributes of builders and their structures. We found that 47 fiddler crab species build at least one type (or subtype) of structure, including chimneys, hoods, pillars, semidomes, mudballs, and rims. Sedimentary structures show a strong association with sediment type as well as builder front type, genus and sex, but not with fiddler crab clade. Experimental studies have revealed distinct, sometimes multiple functions for some of these structures (e.g., female attraction, reduction of aggressive behavior and/or landmark orientation); however, most studies have been observational leaving the proposed functions of these structures for many species untested. Both field and laboratory experiments as well as observational studies can help us to better understand these sedimentary structures and their role in fiddler crab behavior and ecology. [ABSTRACT FROM AUTHOR]

This study was conducted from October 2017 to March 2018 in Mo O territorial waters, Tran De district, Soc Trang province to contribute data of burrow morphology and utilization of the species Periophthalmodon schlosseri that was one of the important economical fish species in the Mekong Delta. The burrow morphology and dimensions were obtained by analyzing 30 casting burrows molded by polyester resin. The burrow utilization was determined by analyzing casting burrows and observing activities of fish in its habitats. The analysis result showed that burrows of this fish were various in shapes such as U, I, and J. The burrow had 1-2 opening with large mound made from mud pellets, and 0-1 bulbous chamber. Dimensions of the chamber did not display seasonal and spatial changes, however, they varied with burrow shape. Furthermore, the burrow dimensional variations did not change with the interaction of season, studied sites, and shape variables. This fish used burrows as a shelter for spawning and avoiding predators. The results can be used for further research on the artificial reproduction of this species. [ABSTRACT FROM AUTHOR]

Branched, sinusoidal burrows assigned to Sinusichnus cf. seilacheri Knaust et al. 2016; occur in Upper Ordovician (Hirnantian) carbonates on Anticosti Island. These are abundant and monospecific at the base of the Oncolite Bed of the uppermost Ellis Bay Formation, marking a regional discontinuity surface during the multiphase Ordovician mass‐extinction event. In contrast to Mesozoic and Cenozoic records of Sinusichnus, commonly attributed to the activity of decapod and isopod crustaceans, the burrow systems from Anticosti Island were probably produced by other arthropods of unknown affinity. A combined dwelling, locomotion and feeding behaviour of their trace maker is assumed. This is the oldest record of the ichnogenus Sinusichnus, previously only known since the Triassic, and its first evidence from North America. [ABSTRACT FROM AUTHOR]

During an actuopalaeontological study, numerous resin casts were made in the Bay of Safaga (Red Sea, Egypt). This yielded, among others, two burrow replicas of a species of the axiid genus Paraxiopsis de Man, 1905 from coral carpets in 26 and 28 m water depth, respectively. In addition, one specimen was captured while digging up one cast, a second was entombed in the other resin cast. A new species is described based on the captured specimen. It is most similar to P. austrinus Sakai, 2004, but differs in the armature of the carapace carinae and cheliped. The burrows, with up to 20 surface openings, have an irregular shape and cross-sections, no wall lining, and reach to a sediment depth of 18 cm. [ABSTRACT FROM AUTHOR]

Plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae) are endemic fossorial vertebrates in the Qinghai–Tibetan Plateau alpine meadow ecosystem. Their different burrowing activities together transform soil structure and then significantly change the landscape of meadow ecosystem. However, how their burrowing activities impact greenhouse gas (GHG) emissions and the pattern of GHG emissions between different types of tunnel burrowing still remain obscure. In this study, we conducted in situ measurements quantitatively investigating the impacts of the different burrowing activities of zokors and pikas on three main GHG CO2, CH4, and N2O from an alpine meadow ecosystem in southeastern Qinghai–Tibetan Plateau. Our results showed that zokor hummocks and pika burrows were sources of CO2 and N2O and sinks of CH4. Zokors burrowing increased N2O in the atmosphere, decreased CO2, and enhanced CH4 absorbing, while pikas burrowing increased N2O in the atmosphere and enhanced CH4 absorbing. Considering the controversial role of fossorial vertebrates in Qinghai–Tibetan Plateau, this study also shed lights on effective management of animal activities with the aim of stabilizing or increasing ecosystem carbon sequestration. [ABSTRACT FROM AUTHOR]

To date according to the registration work, the number of the Russian desman determined actually is 588 individuals in Mordovia. Based on extrapolation, the total desman population in Mordovia is about 1,400 individuals. We may assume that the most of the desman population is concentrated on floodplain lakes and reclamation canals. The highest density of the desman population in Mordovia was recorded in Krasnoslobodsky and Temnikovsky Districts (10.5 and 8.2 burrows per km, respectively). About 400 animals may live on the shore of the rivers Vad, Partsa, Yavas, Vindrey, Nuluy, and Kundybolka. The mean value of density of the desman population on the rivers was 0.9 burrows per km of the coastline, which corresponded to habitat quality class IV (0.5-5 burrows per km). The distribution of habitats across river basins is extremely uneven. The main part of the desman population is restricted to the Moksha basin (more than 1,350 individuals), and in the Alatyr basin (left tributary of the Sura River) just twenty individuals were recorded. [ABSTRACT FROM AUTHOR]

Severe weather events, such as long‐term droughts, are challenging for many freshwater species. To survive drought, freshwater crayfish tend to inhabit shelters or burrows where they can remain in contact with water or high humidity environments. However, it is not known whether embryogenesis or post‐embryonic development can occur without free standing water.To address this question, three experiments were conducted using artificial burrows with high air humidity and using marbled crayfish (Procambarus virginalis Lyko, 2017) as a model species. Marbled crayfish are capable of parthenogenetic reproduction, burrow extensively and are able to travel long distances over land. In the first experiment, ovigerous females were transferred to simulated burrows without free water, but with high air humidity. A control group of females were kept in burrows with free water. Successful hatching was achieved in both groups.In the second experiment, ovigerous females were transferred to simulated burrows with no free water but high air humidity and post‐embryonic development were observed. Following successful hatching, offspring moulted to the second developmental stage (stage 2 juveniles). Stage 2 juveniles remained viable without free water for 20 days, but further development was not observed. However, when some of these stage 2 juveniles were placed back into fully aquatic conditions (experiment 3), they moulted to stage 3 within 4 to 8 days.These results demonstrated the ability of marbled crayfish to undergo terminal phases of embryogenesis, including hatching, as well as early post‐embryonic development under high air humidity conditions only. Post‐embryonic development was suspended in the absence of free water, and successfully resumed when re‐immersed.This similar ability to tolerate drought‐like conditions during post‐embryonic development may also occur in other crayfish species, especially primary burrowers. This unprecedented life history trait may be crucial for inhabiting ecosystems with rapidly changing water regimes. In drying climates, it may confer advantages on some crayfish species (including some invasive species) over others. [ABSTRACT FROM AUTHOR]

A new method for studying the activity of semiaquatic mammals using digital portable voice recorders has been developed. Previously, actographs and night-vision devices were used to study semiaquatic mammals near their burrows. This method allows the mammal activity registration directly in the burrows. The use of voice recorders makes it possible to accurately determine whether the burrow system is inhabited or non-inhabited. In addition, it has become possible to identify the day-night time intervals during which the animals are the most or least active. The new method was tested on the Russian desman (Desmana moschata). Therefore, to identify the burrows in which the recorders were to be installed, the burrows were probed. A probe is a pole pointed at one end with a T-shaped handle at the other end. The researcher's task is to detect the entrance to the burrow, usually under water. And then the direction of the underground passage is determined by means of the probe. For this purpose, the ground is pierced to detect the hollows in the burrow with the probe starting from the burrow entrance (the probe falls through unevenly). At a distance of 2-3 meters from the burrow, in some cases largely depending on the burrow length, the ground is dug up above the burrow in the form of a small well, 10-15 cm in diameter. A digital voice recorder was placed vertically in this well, so that the microphone was directed down towards the burrow. Desman noises can be characterized as short series formed as a sequence of contiguous short peaks of 15-25 seconds with 5 second interruptions formed by regular waves of breathing and its movement noises. Desman noises differ by mean amplitude and duration on oscillograms. As a rule, the noise audibility ranges from 1 to 3 minutes. [ABSTRACT FROM AUTHOR]

Globally, earth embankments are used to protect against flooding. Raised above the surrounding water table, these embankments make ideal habitats for many burrowing animals whose burrows can impact their structural integrity. Ground Penetrating Radar (GPR) is commonly used to identify and map animal burrows and other small cavities. However, the depth of investigation of a GPR survey can be severely limited in saline and clay-rich environments, soil properties commonly associated with flood embankments. In contrast, Electrical Resistivity Tomography (ERT) can image subsurface voids in conductive ground conditions but has been rarely used to image animal burrows. Here we aim to assess the efficacy of ERT and GPR to image two badger burrow networks, called 'setts', located in clay embankments on the River Ouse, Yorkshire, UK. The two setts were excavated to validate the geophysical results, and the soil was characterised through logging and geotechnical analysis to develop a ground model of the site. We find that ERT can accurately resolve tunnels down to 1.5 m depth, map the structure of a multi-entrance badger sett and successfully identify the end of the tunnels. This result compares favourably to the GPR surveys, which mapped all but the deepest tunnels, limited by its penetration depth due to clay soils. Our results show that ERT can be used as a primary survey tool for animal burrows in clay-rich environments and can be validated using co-located GPR surveys if penetration depth is sufficient. The implications of this study may allow embankment managers to map burrow networks, assess flood embankment stability, minimise repair costs, and reduce unexpected failures during flood events. Additionally, a better understanding of how, for example, local heterogeneities impact badgers' burrow geometry may be achievable using these geophysical methods, as they provide a non-destructive, repeatable method for imaging setts. • Badger setts can be mapped using non-intrusive geophysical methods in clayey soils • Electrical Resistivity Tomography can image and map badger burrows up to 1.5 m deep • Ground Penetrating Radar strongly complements ERT, but penetration depth is limiting • Combining geophysical methods can significantly increase confidence in burrow maps • Geophysics can image interaction between badger burrows and variations in soil types [ABSTRACT FROM AUTHOR]

Protovirgularia is an old name for prominent trace fossils common throughout the Phanerozoic and fascinating geologists for about 175 years. Repeatedly described under different names, taxonomic work from the 1990's argued for the inclusion of several morphologically similar ichnogenera in Protovirgularia. A critical review of the type specimens of the included ichnospecies and their synonyms confirms the validity of five ichnospecies by applying uniform ichnotaxobases. A morphometric analysis of key parameters assists in the distinction of these ichnospecies. The type ichnospecies Protovirgularia dichotoma , generally regarded as a trail, is better qualified as a trackway, in contrast to the remaining ichnospecies, which represent shallow burrows. Beside the habitus of the burrow, the shape, density and orientation of its sediment pads (or chevrons) and their ornamentation allow the distinction of P. pennata , P. rugosa , P. longespicata and P. bifurcata. Compound forms resulting from locomotion and resting are rejected as an ichnotaxobase. The enigmatic nature of Protovirgularia led to speculations about its origin, including various body-fossil interpretations (e.g., sea pens and annelids). Now widely accepted as a trace fossil, the interpretation of its producer varied and became oversimplified based on an experiment made with protobranch bivalves. Several characteristics support an interpretation of many Protovirgularia specimens as arthropod-produced (e.g., malacostracan crustaceans) instead of molluscs, which is in alignment with suggestions by older work. A literature review of verifiable illustrations of trace fossils conformable with one of the five ichnospecies not only confirms their recurrence and validity as endmembers, but also highlights stratigraphical and palaeoenvironmental trends. [ABSTRACT FROM AUTHOR]

A total of 47 active badger burrows in the Southeastern Bulgaria were described in order to find whether there are preferences to terrain exposure for its digging activity. The most of the dens were found on terrain with south exposure - 23.4%, followed by these on the east and west side -19.15% each. The dens faced to these three directions, together with these to intercardinal directions connected with south, represented 80.85% of the active badger dens found. A tendency in the preference of the European badger to the southern exposure of the terrain for its digging activity in the region of Southeastern Bulgaria was established. [ABSTRACT FROM AUTHOR]

Seven earthworm ecological categories, including anecics, endogeics and epigeics, were defined by Marcel Bouché in 1972 based only on morpho-anatomical characteristics measured on European lumbricids. These categories had an outstanding success, and their use was generalized even outside of Europe. However, most of the time, only the three main categories are used, and over two decades, these categories have been considered functional groups, i.e. to presume how earthworms influence the soil functioning. Moreover, this relationship between ecological categories and functional groups is seldom tested and often uncritically accepted by soil biology researchers. It is then not surprising to observe unexpected trends when earthworm species are gathered in ecological categories to, for instance, analyze burrow systems or cast properties. We believe it is time to acknowledge that ecological categories are not functional, because they were not made for this purpose. We also propose three future directions in order to either improve our knowledge on the functional effects of earthworms or to build new authentically functional groups: (i) going back to the seven initial ecological categories to provide greater accuracy than the usage of the simplified three-level classification; (ii) testing, for a set of selected species, the functionality of the groups, being ecological categories or new tailored ones; and (iii) using trait-based approach in order to study the correlation between some earthworm traits and main soil functions. [ABSTRACT FROM AUTHOR]

The Plains vizcacha (Lagostomus maximus) is one of the largest rodents in South America. They live in communal burrow systems (vizcacheras) shaped by complex subterranean galleries which produce a strong impact on the local landscape. This paper presents the results of an actualistic study conducted with abandoned vizcacheras from the Pampas region of Argentina. The main objective is to evaluate the role of this rodent in the formation of the fossil record. Results indicate that the Plains vizcacha is responsible for the mixing, accumulation, and transport of materials; such as sticks, caliche, dung, feces, and abundant bone remains. Their burrowing activity and the accumulating habits, modifies the landscape, creating environments conducive to the buildup of objects and the reuse by different animals. These characteristics result in very complex associations of materials of different origins; making this rodent an important taphonomic agent with the potential to significantly impact the fossil record. [ABSTRACT FROM AUTHOR]

The fossil burrow Dolopichnus, capped by an ash layer, was collected ∼0.6 m below the Permian–Triassic Boundary at the Lung Cam section in North Vietnam. The burrow occurs at the top of Bed 9, directly below the stepped extinction in foraminifera that marks initiation of the global perturbations related to the end-Permian extinction event. Dolopichnus is a plug-shaped burrow, possessing lining and fills. This specimen was found capped by an undisrupted bentonite layer. The main chamber has internal structure throughout indicative of benthic organisms overcoming living pressures of repeated ash falls, which can be applied to paleoenvironmental research across different regions and times, including the recent. [ABSTRACT FROM AUTHOR]

Abstract Our objective was to compare the efficiency of indirect (burrow density, size, depth and occupation rate) and direct (emersion from burrows, tolerance distance from humans and number of foraging crabs) metrics of the ghost crab Ocypode quadrata for urbanization impact assessments. We sampled six beaches during high and low tourism seasons along a gradient of human pressure: high impact (urbanized), medium impact (intermediate) and low impact (non-urbanized). We found that the urbanization index and temperature explained the burrow density and size regardless of the bias related to the burrow occupation rate (∼60%) and counting period (diurnal or nocturnal). Moreover, the number of nocturnal foraging crabs explained most (57%) of the dissimilarity among the beaches under different levels of human impact. Thus, the counting of foraging crabs at night was found to be a relevant metric for beach impact evaluation. We strongly recommend integrating the counting foraging crabs with traditional burrow measurements (burrow density and size) in impact assessments of sandy beaches. Graphical abstract Image 1 Highlights • Indirect and direct metrics of a ghost crab were compared for impact assessment. • Sampling included six beaches in a gradient of human pressure. • Burrow density and size were significantly predicted by the urbanization index. • Number of foraging crabs explained most of the dissimilarity among the beaches. • Counting foraging crabs is an alternative metric for beach impact evaluations. [ABSTRACT FROM AUTHOR]