Armadillidium Vulgare Research Articles

Heterogeneous distribution of sex ratio distorters in natural populations of the isopod Armadillidium vulgare.

In the isopod Armadillidium vulgare, many females produce progenies with female-biased sex ratios, owing to two feminizing sex ratio distorters (SRD): Wolbachia endosymbionts and the f element. We investigated the distribution and population dynamics of these SRD and mitochondrial DNA variation in 16 populations from Europe and Japan. Confirming and extending results from the 1990s, we found that the SRD are present at variable frequencies in populations and that the f element is overall more frequent than Wolbachia. The two SRD never co-occur at high frequency in any population, suggesting an apparent mutual exclusion. We also detected Wolbachia or the f element in some males, which probably reflects insufficient titer to induce feminization or presence of masculinizing alleles. Our results are consistent with a single integration event of a Wolbachia genome in the A. vulgare genome at the origin of the f element, which contradicts an earlier hypothesis of frequent losses and gains. We identified strong linkage between Wolbachia strains and mitochondrial haplotypes, but no association between the f element and mitochondrial background. Our results open new perspectives on SRD evolutionary dynamics in A. vulgare, the evolution of genetic conflicts and their impact on the variability of sex determination systems.

Agamermis sp. (Nematoda: Mermithidae) parasitizing Armadillidium vulgare (Crustacea: Isopoda) in Argentina.

The Mermithidae is a family of nematodes parasitic in many kinds of insects, spiders, leeches, crustaceans and other invertebrates throughout the world. While conducting an assay with entomopathogenic nematodes, we found Armadillidium vulgare (Crustacea: Isopoda) individuals to be infected with Agamermis sp., marking the fourth known discovery of a mermithid infection in the order Isopoda. In this work, we contribute with an 18S rDNA sequence of the isolated nematode and the morphological and morphometrical characterization of the juveniles.

Weak evidence that asset protection underlies temporal or contextual consistency in boldness of a terrestrial crustacean

In recent years, many studies have investigated the potential state dependence of individual differences in behaviour, with the aim to understand the proximate and ultimate causes and consequences of animal personality. Among the potential state variables that could affect behavioural expression is size and mass, but few studies have found associations at the among-individual levels. Insufficient sampling and incorrect analysis of data are cited as impediments to detecting correlations, if they exist. Here, we conducted a study using 100 pillbugs (Armadillidium vulgare) and assayed their defensive behaviour 24 times each over time and across familiarity contexts, to test the asset protection hypothesis that predicts a negative correlation between boldness and mass, and with increases in mass over time. Multivariate mixed models revealed that despite mostly consistent individual behavioural differences over time (modest slope variance) and across contexts (near-parallel reaction norms), and 18-fold range in starting mass, there was no correlation between individual mean mass and boldness. However, individuals that gained more mass over time may have been more ‘shy’ compared to those gaining less mass, but the correlation was weak and observed variation in mass gain was small. There was also a mean level trend of increasing shyness over time that was coincident with mean level mass increases over time. Together, our study provides weak evidence for the asset protection hypothesis, whereby individuals that accumulate more resources are thought to protect them through risk averse behaviour.Significance statementIndividual variation in ‘state’, such as mass or energy reserves, is thought to be a predictor of individual differences in behaviour that are consistent over time. However, few studies reveal such links, and several studies suggest insufficient sampling may explain null results in most studies. We studied 100 animals sampled 24 times each in a controlled setting to reveal stable individual differences in mean behaviour over time and across contexts; however, individual behaviour was unrelated to large differences in individual mass but weakly related to increases in mass through time whereby individuals became more shy and those growing faster were somewhat more shy. Our results provide little evidence for the asset protection hypothesis.

Microstructure, mechanical properties and elemental composition of the terrestrial isopod Armadillidium vulgare cuticle

The exoskeletons of crustaceans are essential for providing protection from predators and other environmental threats. Understanding the structure and mechanical behavior of their natural armor could inspire the design of lightweight and high toughness synthetic materials. Most published work has focused on marine crustacea rather than their terrestrial counterparts, which are exposed to a multitude of unique threats. The interest in the terrestrial isopod Armadillidium vulgare (A. vulgare) has grown but the interrelationship between the microstructure, chemical composition, and mechanical properties has not been thoroughly investigated. Thus, this study aims to elucidate missing details concerning this biological mineralized composite. Exoskeleton specimens were fixated to preserve the intrinsic protein structure. We utilize scanning electron microscopy for microstructure analysis, Raman spectroscopy for elemental analysis, and nanoindentation property mapping to achieve mechanical characterization. The naturally fractured A. vulgare exoskeleton cross-section reveals four subregions with the repeating helicoidal ‘Bouligand’ arrangement most prominent in the endocuticle. The hardness and reduced modulus distributions exhibit a through-thickness exponential gradient with decreasing magnitudes from the outermost to the innermost layers of the exoskeleton. The Raman spectra show a graded spatial distribution of key constituents such as calcium carbonate across the thickness, some of which are consistent with the mechanical property gradient. Potential microstructure, elemental composition, and mechanical property relationships are discussed to explain how the hierarchical structure of this nanolaminate armor protects this species.

Immune priming in Armadillidiumvulgare against Salmonellaenterica: direct or indirect costs on life history traits?

Invertebrate immune priming is defined as an enhanced protection against secondary pathogenic infections when individuals have been previously exposed to the same or a different pathogen. Immune priming can be energetically costly for individuals, thus impacting trade-offs between life-history traits, like reproduction, growth, and lifetime. Here, the reproductive cost(s) and senescence patterns of immune priming against S.enterica in the common woodlouse A.vulgare (Crustacea, Isopoda) were investigated. Four different groups of females were used that either (1) have never been injected (control), (2) were injected twice with S.enterica (7 days between infections), (3) were firstly injected with LB-broth, then with S.enterica, and (4) females injected only once with S.enterica. All females were allowed to breed with one non-infected male and were observed for eight months. Then, the number of clutches produced, the time taken to produce the clutch(es), the number of offspring in each clutch, the senescence biomarkers of females, and parameters of their haemocytes were compared. The result was that immune priming did not significantly impact reproductive abilities, senescence patterns, and haemocyte parameters of female A.vulgare, but had an indirect effect through body weight. The lighter immune primed females took less time to produce the first clutch, which contained less offspring, but they were more likely to produce a second clutch. The opposite effects were observed in the heavier immune primed females. By highlighting that immune priming was not as costly as expected in A.vulgare, these results provide new insights into the adaptive nature of this immune process.

Comparative exploratory movements of two terrestrial isopods (suborder: Oniscidea), in response to humidity and availability of food

Abstract Unfavourable conditions within familiar environments may prompt organisms to make forays into other habitats, at least temporarily. This behaviour is in turn linked to key demographic processes such as immigration, emigration, and eventually, metapopulation dynamics. How such movements are triggered by environmental conditions (much less their interaction effects) has rarely been experimentally tested. To address this, we examined how environmental conditions (3 levels of food and 3 levels of humidity) within a microcosm affect the movements of two species of isopods (Armadillidium vulgare and Porcellio scaber) out of their familiar habitat. We used web-camera checkpoints to record the movements of individually marked animals as they conducted forays along corridors that lead to new, unused habitats. Thirty-six trials were run in total for each species, with each trial involving 16 animals (8 ♂♂, 8 ♀♀). Relatively unfavourable conditions of low humidity, low food levels, and their interaction prompted changes to all the foray metrics we measured. However, different levels of mobility and tolerance to desiccation between the two species also appeared linked to the degree of responses, e.g., Porcellio demonstrated a greater tendency to depart from familiar habitat under low humidity, possibly due to their superior mobility and greater susceptibility to desiccation. This study improves our understanding of how different environmental conditions act in concert to affect the exploratory movements away from familiar habitat, and how these responses differ even for closely-related species.

Comparison of exploratory behavior of two different animal species: woodlice (Armadillidium vulgare) and Rats (Rattus norvegicus)

Exploratory behavior is a commonly used instrument in the study of animal behavior in the laboratory, usually using rodents. The goal of the present study was to investigate the exploratory behavior of woodlice (Armadillidium vulgare) and compare to the behavior of rats (Rattus norvegicus). For this, we used two of two common rat laboratory tests: the square open-field and another inspired in the rat Light/Dark box. In a first test, rats were submitted to a square open-field; woodlice were also submitted to an open-field adapted to their size. In a second test, rats were submitted to a Light/Dark box and the woodlice were submitted to a Dry/Moist box designed to be equivalent to the rat apparatus but adapted to woodlice size. Results of the first test showed both rats and woodlice explored the square open-fields in similar ways, both in terms of frequencies of entries in the areas and also in terms of the time spent in them. Subjects of both species occupied the corners more than the areas close to the walls and these more than the central areas. Results of the second test showed a striking resemblance: Both species spent more time in the safe areas (dark or moist) and less time in the aversive areas (light or dry). Given this similarity, woodlice could be used as laboratory animals for behavioral studies with the advantages of occupying little room in animal places, are easy to catch in many places around university campuses and cost little to be fed.

A Generalized Distribution Interpolated between the Exponential and Power Law Distributions and Applied to Pill Bug (Armadillidium Vulgare) Walking Data

A Generalized Distribution Interpolated between the Exponential and Power Law Distributions and Applied to Pill Bug (Armadillidium Vulgare) Walking Data

Postmortem Evaluation of Rabbit Carcasses Using Insect Populations in Keffi Nasarawa State, Nigeria

Untimely, forceful, and unexpected death is inevitable and common worldwide. Evidence for causes of death may be obtained through the knowledge of insects’ successional pattern and postmortem interval on dead carcasses. Two rabbits (Lepus cuniculus) weighing 2.5 kg each were used as the experimental animals. The rabbits were sacrificed by poisoning and stabbing, postmortem evaluation was achieved by taking record of the insect’s successional pattern. The insects’ successional pattern revealed the following insects’ species in order in which they arrived on the carcasses: Musca domestica, Lucilia sericata, Chrysomya albiceps, Dermestes maculatus, and Armadillidium vulgare (usual sp). The family Formicidae were represented by two unidentified species. M. domestica arrived first on the stabbed carcass while L. sericata on poisoned carcass. A total of 105±50 insects were collected throughout the study period, with stabbed rabbit contributing 61±10 and poisoned 44±60 insects’ species. Variation in the number of forensically important insects’ species encountered in the study site did not show any significant difference (p>0.05) in relation to each decomposition stage. There was however a significant difference (p<0.05) between insects’ relative abundance and mode of killing. Insect evidence was found 3 minutes after death on the stabbed carcass and 3 days after on the poisoned carcass. The study has shown that insects' population can be used to establish postmortem evidence in rabbit carcasses.

Feminising Wolbachia disrupt Armadillidium vulgare insulin-like signalling pathway.

The endosymbiont Wolbachia feminises male isopods by making them refractory to the insulin-like masculinising hormone, which shunts the autocrine development of the androgenic glands. It was, therefore, proposed that Wolbachia silences the IR receptors, either by preventing their expression or by inactivating them. We describe here the two IR paralogs of Armadillidium vulgare. They displayed a conventional structure and belonged to a family widespread among isopods. Av-IR1 displayed an ubiquist expression, whereas the expression of Av-IR2 was restricted to the gonads. Both were constitutively expressed in males and females and throughout development. However, upon silencing, altered gland physiology and gene expression therein suggested antagonistic roles for Av-IR1 (androinhibiting) and Av-IR2 (androstimulating). They may function in tandem with regulating neurohormones, as a conditional platform that conveys insulin signalling. Wolbachia infection did not alter their expression patterns: leaving the IRs unscathed, the bacteria would suppress the secretion of the neurohormones, thus inducing body-wide IR deactivation and feminisation. Adult males injected with Wolbachia acquired an intersexed physiology. Their phenotypes and gene expressions mirrored the silencing of Av-IR1 only, suggesting that imperfect feminisation stems from a flawed invasion of the androstimulating centre, whereas in fully feminised males invasion would be complete in early juveniles. TAKE AWAY: Two antagonistic Insulin Receptors were characterised in Armadillidium vulgare. The IRs were involved in androstimulating and androinhibiting functions. Wolbachia-induced feminisation did not prevent the expression of the IRs. Imperfectly feminised intersexes phenocopied the silencing of Av-IR1 only. Wolbachia would deactivate the IRs by suppressing neurosecretory co-factors.

Acautalides A-C, Neuroprotective Diels-Alder Adducts from Solid-State Cultivated Acaulium sp. H-JQSF.

The solid-state cultivation of Acaulium sp. H-JQSF isolated from Armadillidium vulgare produces acautalides A-C (1-3) as skeletally unprecedented Diels-Alder adducts of a 14-membered macrodiolide to an octadeca-9,11,13-trienoic acid. The acautalide structures, along with the intramolecular transesterifications of 1-acylglycerols, were elucidated by mass spectrometry, nuclear magnetic resonance, chemical transformation, and single-crystal X-ray diffraction. Compounds 1-3 were found to be neuroprotective with antiparkinsonic potential in the 1-methyl-4-phenylpyridinium-challenged nematode model, with the magnitude impacted by the glycerol esterification.

Characterization of a Sex-Determining Region and Its Genomic Context via Statistical Estimates of Haplotype Frequencies in Daughters and Sons Sequenced in Pools.

Sex chromosomes are generally derived from a pair of autosomes that have acquired a locus controlling sex. Sex chromosomes may evolve reduced recombination around this locus and undergo a long process of molecular divergence. At that point, the original loci controlling sex may be difficult to pinpoint. This difficulty has affected many model species from mammals to birds to flies, which present highly diverged sex chromosomes. Identifying sex-controlling loci is easier in species with molecularly similar sex chromosomes. Here we aimed at pinpointing the sex-determining region (SDR) of Armadillidium vulgare, a terrestrial isopod with female heterogamety (ZW females and ZZ males) and whose sex chromosomes appear to show low genetic divergence. To locate the SDR, we assessed single-nucleotide polymorphism (SNP) allele frequencies in F1 daughters and sons sequenced in pools (pool-seq) in several families. We developed a Bayesian method that uses the SNP genotypes of individually sequenced parents and pool-seq data from F1 siblings to estimate the genetic distance between a given genomic region (contig) and the SDR. This allowed us to assign more than 43 Mb of contigs to sex chromosomes, and to demonstrate extensive recombination and very low divergence between these chromosomes. By taking advantage of multiple F1 families, we delineated a very short genomic region (∼65 kb) that presented no evidence of recombination with the SDR. In this short genomic region, the comparison of sequencing depths between sexes highlighted female-specific genes that have undergone recent duplication, and which may be involved in sex determination in A. vulgare.

Ecotoxicity of triclosan in soil: an approach using different species.

Triclosan is an antimicrobial agent widely used in personal care products and an emerging contaminant with potential to have harmful effects to edaphic organisms. This study aimed to evaluate the impacts of exposure to triclosan on the microbiota, plants, and edaphic animals using isolated bioassays and a microcosm scale representation (multispecies system). Among the isolated bioassays, the phytotoxicity test with Lactuca sativa, avoidance test with Eisenia andrei, and acute toxicity with E. andrei and Armadillidium vulgare were used. The multispecies system used seeds of L. sativa and Sinapis alba, together with earthworms and terrestrial isopods. This system also evaluated microbial activity through alkaline phosphatase and the metabolic profile using Ecoplate™, BIOLOG microplates. Exposure to triclosan impacted seedling growth in the isolated bioassay and germination and root growth in the microcosm scale assay; it also caused mortality in terrestrial isopods, earthworm avoidance and alteration of alkaline phosphatase, and the consumption profile of carbohydrates and carboxylic acids in the microbiota. The ecotoxicological effects evaluated in the multispecies system were perceived even in low concentrations of triclosan, indicating that the interaction of this xenobiotic with the environment and organisms in a more realistic scenario can compromise ecosystem services.

Bioassays for the evaluation of reclaimed opencast coal mining areas.

This study aimed to use bioassays (single and multispecies) with organisms from different trophic levels to assess soil quality in reclaimed coal mining areas. Soil samples were collected from four sites: two sites with recent reclaim processes (one using topsoil and other using clayey soil), an natural attenuation site, and a control soil. The evaluated parameters were divided into (1) ecotoxicological tests (avoidance test with Eisenia andrei (earthworms) and Armadillidium vulgare (isopods); germination test with Sinapis alba seeds (mustard); reproduction tests with Folsomia candida (collembolans); bacterial toxicity test); (2) population and community assessments (a fungal count; microbial community analysis using Biolog EcoPlatesTM); (3) microcosms scale evaluation (the MS-3 multispecies system); and (4) chemical analysis (soil parameters, soil metal, and cations and anions in soil leachate). Results pointed to toxicity in the natural attenuation site that compromised of habitat function, probably due to low pH and low nutrient levels. The most recent reclaim process, using topsoil and clay soil, improved soil quality and fertility, with a further increase in habitat quality and heterogeneity. This study shows that some techniques used to reclaim degraded mining areas are effective in rebuilding habitats, sustaining soil biota, and reestablishing ecosystem services.

Importance of non‐native isopods and other terrestrial prey resources to steelhead/rainbow trout Oncorhynchus mykiss in coastal streams in Big Sur, California

AbstractTerrestrial invertebrates provide important prey subsidies to many stream fishes. Non‐native invertebrates are widespread in many ecosystems, yet they have received little attention in studies of subsidies to stream food webs. We sampled coastal basins in Big Sur, California, to determine the importance of non‐native isopods and other terrestrial invertebrates in the summer diet of steelhead/rainbow trout (Oncorhynchus mykiss) and to estimate the density of isopods along streambanks. Terrestrial invertebrates contributed more than 40% of the energetic value of O. mykiss stomach contents at most sites and up to 75% at some locations. Non‐native isopods Armadillidium vulgare or Porcellio scaber occurred at all sites, reaching mean densities of up to 13 individuals/m2 on streambanks, and accounted for up to 20% of the energy in the diet. The proportion of non‐native isopods in the diet was positively correlated with their density at a site, and the frequency and energetic value of terrestrial invertebrates and non‐native isopods in O. mykiss diets increased with fish size. In terms of the broader diet, the energetic value and taxonomic composition of stomach contents varied among sites but there was no major geographic pattern or trend to the variation, and overall O. mykiss diets were generally similar across the region. Our results highlight that non‐native terrestrial invertebrates may provide a considerable but overlooked subsidy to stream fishes.

Effects of Dysbiosis and Dietary Manipulation on the Digestive Microbiota of a Detritivorous Arthropod.

The crucial role of microbes in the evolution, development, health, and ecological interactions of multicellular organisms is now widely recognized in the holobiont concept. However, the structure and stability of microbiota are highly dependent on abiotic and biotic factors, especially in the gut, which can be colonized by transient bacteria depending on the host’s diet. We studied these impacts by manipulating the digestive microbiota of the detritivore Armadillidium vulgare and analyzing the consequences on its structure and function. Hosts were exposed to initial starvation and then were fed diets that varied the different components of lignocellulose. A total of 72 digestive microbiota were analyzed according to the type of the diet (standard or enriched in cellulose, lignin, or hemicellulose) and the period following dysbiosis. The results showed that microbiota from the hepatopancreas were very stable and resilient, while the most diverse and labile over time were found in the hindgut. Dysbiosis and selective diets may have affected the host fitness by altering the structure of the microbiota and its predicted functions. Overall, these modifications can therefore have effects not only on the holobiont, but also on the “eco-holobiont” conceptualization of macroorganisms.

Influence of saprophages (Isopoda, Diplopoda) on leaf litter decomposition under different levels of humidification and chemical loading

The paper presents a study about the influence of two saprophage groups (Isopoda, Diplopoda) on leaf litter decomposition under different levels of humidification and chemical stress. Because of their worldwide distribution, we focused on the common pillbug Armadillidium vulgare (Latreille, 1804) (Isopoda, Armadillidiidae), and the common millipede species Rossiulus kessleri (Lohmander, 1927) (Julida, Julidae). The function of environment creation by the given saprophages, as destructors of dead plant matter, supporting such ecosystem services as soil fertility improvement and nutrients’ turnover, is highlighted. To conduct the experiment, the animals were collected manually and using pitfall trapping. In order to bring the experimental conditions closer to the natural, the individuals were not sexed. The maximum consumption of leaf litter by woodlice was recorded in the conditions with adequate moisture (0.5 mL of distilled water per box) and amounted to 2.52 mg/10 individuals per day, which exceeds its consumption with low and increased moisture, respectively, by 1.82 and 1.24 times. As for the effect of interaction, the consumption of maple litter with optimal moisture (4.77 mg/10 individuals per day) was the greatest. The largest absolute difference between broad-leaved tree species in the average weight of leaf litter consumed by woodlice was between maple leaf litter and oak leaf litter, the minimum – between robinia leaf litter and oak leaf litter. According to the results of the obtained data (Diplopoda), it can be stated that there is a statistically significant effect of chemical stress and discrepancy of the average zinc content in the object of study (in Diplopoda and their faecal pellets). We found that the diet provided did not affect the distribution of zinc in Diplopoda under conditions of chemical stress. According to the results of pairwise comparisons, we determined that the zinc content in the Diplopoda clearly differs for control and almost every concentration of zinc sulfate solution – 0.03 and 0.15 g/L, the samples of which do not form a homogeneous group. The species composition, abundance and distribution in space of soil invertebrates are informative indicators which reflect the ecological state of soils, intensity in development of soil horizons as well as intensity of processes occurring in them.

Two new azaphilone pigments from Talaromyces albobiverticillius and their anti-inflammatory activity

Two new azaphilone pigments, talaralbols A and B (3 and 7), along with five known azaphilone metabolites (1, 2, and 4–6), were isolated from the culture of Talaromyces albobiverticillius associated with the isopod Armadillidium vulgare. Their structures were elucidated by a combination of 1 D and 2 D NMR data, ECD calculations, chemical transformations, and NMR data analogy with model compounds. Talaralbol A (3) showed a moderate inhibition on the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells with the inhibitory rate being 31.0% at the concentration of 10 μM.

Immune priming depends on age, sex and Wolbachia in the interaction between Armadillidium vulgare and Salmonella.

The protection conferred by a first infection upon a second pathogenic exposure (i.e. immune priming) is an emergent research topic in the field of invertebrate immunity. Immune priming has been demonstrated in various species, but little is known about the intrinsic factors that may influence this immune process. In this study, we tested whether age, gender and the symbiotic bacterium Wolbachia affect the protection resulting from immune priming in A. vulgare against S. enterica. We firstly primed young and old, symbiotic and asymbiotic males and females, either with a non-lethal low dose of S. enterica, LB broth or without injection (control). Seven days post-injection, we performed a LD50 injection of S. enterica in all individuals and we monitored their survival rates. We demonstrated that survival capacities depend on these three factors: young and old asymbiotic individuals (males and females) expressed immune priming (S. enterica-primed individuals survived better than LB-primed and non-primed), with a general decline in the strength of protection in old females, but not in old males, compared to young. When Wolbachia is present, the immune priming protection was observed in old, but not in young symbiotic individuals, even if the Wolbachia load on entire individuals is equivalent regardless to age. Our overall results showed that the immune priming protection in A. vulgare depends on individuals' states, highlighting the need to consider these factors both in mechanistical and evolutionary studies focusing on invertebrate's immunity.

Tamarisk Alters Arthropod Composition, but has Little Negative Effect on Richness and Abundance in Southwestern Colorado

Riparian corridors are vulnerable to invasion by non-native plant species that can alter arthropod communities and ecological functions. Tamarisk (Tamarix4 spp. L.) replaced native riparian vegetation on 1.6 million acres in the southwestern United States. Our study investigated arthropod communities in three riparian habitats, two dominated by native vegetation (willow (Salix exigua5 Nutt.) in lower floodplain and mixed-native xeroriparian shrubs in upper floodplain) and one invaded by non-native tamarisk in lower floodplain. Tamarisk was predicted to lessen arthropod abundance and richness, change composition, and associate with nonnative arthropods. We sampled 41,124 arthropods identified to 258 taxa and seven functional groups during 2 years along the Dolores River in Colorado. Richness and abundance were not less in tamarisk, but composition differed among the three habitats. Trends varied across taxonomic and functional groups. Lower floodplain habitats, tamarisk and willow, were relatively similar in composition, with large numbers of beetles, hemipterans, detritivores, and herbivores. More ants, pollinators, and greater diversity were in upper floodplain shrub habitat. Tamarisk hosted several non-native arthropods: Armadillidium vulgare (Latreille)6, Cylisticus convexus (De Geer)7, Diorhabda carinulata (Desbrochers)8, and Coniatus splendidulus (Fabricius)9, while willow housed non-native weevils (Otiorhynchus spp. Germar)9. Tamarisk was favored by some non-native arthropods and altered community composition but did not lessen abundance or richness of functional or taxonomic groups. The results highlighted effects of non-native plants on arthropod communities and have implications for conservation of insectivorous riparian wildlife.