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Freshwater crayfish are among the most endangered animal groups in the world. Appropriate management requires an understanding of sampling bias when assessing their distribution and abundance. We evaluated the effectiveness of a variety of sampling methods for detecting freshwater crayfish (genus Euastacus) in situ and potential biases towards individual-level traits associated with these methods. We also experimentally manipulated the presence of crayfish within opera house traps to determine the effects of trap residency on capture rate and the characteristics of crayfish approaching the traps. Baited hoop nets and baited remote underwater video surveys (BRUVS) detected significantly more crayfish than did unbaited video surveys (RUVS). Crayfish captured in baited hoop nets were significantly larger than were crayfish measured in the BRUV and RUV surveys, suggesting that hoop nets were biased to capturing larger animals. The experiment demonstrated that a greater number of crayfish entered empty rather than occupied traps; however, there were no differences in their body sizes. We highlight the importance of optimising sampling for freshwater crayfish to ensure reliable and robust population estimates. This is of critical importance as many have highly restricted ranges and face numerous threats. We contend that this will assist in informing conservation strategies to protect aquatic species at risk.

Anchor scour from shipping is increasingly recognised as a global threat to benthic marine biodiversity, yet no replicated ecological assessment exists for any seabed community. Without quantification of impacts to biota, there is substantial uncertainty for maritime stakeholders and managers of the marine estate on how these impacts can be managed or minimised. Our study focuses on a region in SE Australia with a high proportion of mesophotic reef (30 m), where ships anchor while waiting to enter nearby ports. Temperate mesophotic rocky reefs are unique, providing a platform for a diversity of biota, including sponges, ahermatypic corals and other sessile invertebrates. They are rich in biodiversity, provide essential food resources, habitat refugia and ecosystem services for a range of economically, as well as ecologically important taxa. We examined seven representative taxa from four phyla (porifera, cnidaria, bryozoan, hydrozoa) across anchored and 'anchor-free' sites to determine which biota and which of their morphologies were most at risk. Using stereo-imagery, we assessed the richness of animal forest biota, morphology, size, and relative abundance. Our analysis revealed striking impacts to animal forests exposed to anchoring with between three and four-fold declines in morphotype richness and relative abundance. Marked compositional shifts, relative to those reefs that were anchor-free, were also apparent. Six of the seven taxonomic groups, most notably sponge morphotypes, exhibited strong negative responses to anchoring, while one morphotype, soft bryozoans, showed no difference between treatments. Our findings confirm that anchoring on reefs leads to the substantial removal of biota, with marked reductions of biodiversity and requires urgent management. The exclusion of areas of high biological value from anchorages is an important first step towards ameliorating impacts and promoting the recovery of biodiversity.

PRECIS Eyes with corneal striae had steeper cornea, induced astigmatism, and higher corneal hysteresis, which implies a relationship between striae, corneal shape, and the cornea's resistance to deformation at low intraocular pressures. BACKGROUND Anterior corneal striae (ACS) are associated with low intraocular pressure (IOP). However, the clinical significance of ACS is unclear. Here, we aim to evaluate differences in eyes with striae compared to eyes without striae. METHODS Adults with ACS (cases) and without ACS (controls) ≥8 weeks after glaucoma surgery with an IOP ≤10▒mmHg were enrolled. Optical coherence tomography and optical biometry were performed. Corneal hysteresis (CH), defined as difference in pressure between corneal indentation and reformation in response to an air jet, was obtained by the ocular response analyzer. Hypotony maculopathy (HM) was defined as optic disc swelling, vascular tortuosity attributed to hypotony, or clinical presence of chorioretinal folds confirmed on OCT. RESULTS One-hundred sixteen eyes (76 cases, 40 controls) were included. Cases had a lower IOP compared to controls (6.5±2.3 vs. 8.5±1, P

For decades, precoated heat- and solvent-set tissues have been the preferred method for mending certain types of library and archival materials due to their translucency and ability to be used with...

Freshwater snails usually possess thin unadorned shells lacking structural components such as spines. Exceptions can be found on the high, well-watered islands of the South Pacific. Streams on these islands support a rich freshwater molluscan fauna with several nerite taxa (Neritimorpha: Neritidae) exhibiting extremely long dorsal spines. We sought to assess the defensive capacity of these structures for several co-occurring nerite genera on the Island of Ovalau, Fiji. Our overarching hypothesis was that spines confer a defensive advantage. We tested four predictions for eight common taxa: (i) predator “rich” habitats (the creek entrance) would be dominated by spine-bearing nerites, (ii) spine-bearing species should be smaller in size, (iii) nerites with spines would exhibit lower levels of shell damage and (iv) nerites with spines should invest less in their shells (i.e., their shells should be thinner). Most of these predictions received support. Spine-bearing species dominated the entrance to the creek and were smaller in size. Levels of shell damage were low overall, with 2 of the 3 spinose taxa exhibiting no shell damage, as did many of the nonspinose taxa. Finally, shells of spinose species were 25% thicker, demonstrating increased rather than decreased investment. Taken together, these findings suggest that the elaborate spines of Clithon spp. play a defensive role.

This article responds to Adam Gregerman’s article on covenant theology in recent Jewish–Catholic dialogue by arguing three points: (1) Scripture presents a multiplicity of covenants (rather than a singular “Old Covenant”), which coexist together in complementary ways. (2) This multiplicity produces dynamic tension among the covenants. (3) The tendency in recent theological discussion to describe the New Covenant as a fulfillment of its predecessors lacks a biblical basis.

Marine reserves are an important management tool for conserving local biodiversity and protecting fragile ecosystems such as seagrass that provide significant ecological functions and services to people and the marine environment. With humans placing ever-growing pressure on seagrass habitats, marine reserves also provide an important reference from which changes to seagrass and their ecological assemblages may be assessed. After eight years of protection of seagrass beds (Posidonia australis) in no-take marine reserves (Sanctuary Zones) within the Jervis Bay Marine Park (New South Wales, Australia; zoned in 2002), we aimed to assess what changes may have occurred and assess continuing change through time in fish assemblages within these seagrass meadows. Using baited remote underwater videos (BRUVs), we sampled seagrass fish assemblages at three locations in no-take zones and five locations in fished zones three times from 2010 to 2013. Overall, we observed a total of 2615 individuals from 40 fish species drawn from 24 families. We detected no differences in total fish abundance, diversity, or assemblage composition between management zones, although we observed a significant increase in Haletta semifasciata, a locally targeted fish species, in no-take marine reserves compared with fished areas. Fish assemblages in seagrass varied greatly amongst times and locations. Several species varied in relative abundance greatly over months and years, whilst others had consistently greater relative abundances at specific locations. We discuss the potential utility of marine reserves covering seagrass habitats and the value of baseline data from which future changes to seagrass fish populations may be measured.

Carboranes have been previously noted to distinctively affect the luminescent properties of semiconducting polymers when incorporated into the conjugated backbone. In this report, we use carborane-based poly(fluorene) derivatives as active materials for polymer light-emitting diodes and transistors. Optoelectronic analysis unequivocally shows that carborane does not participate in the π-conjugated network, yet their presence causes major red-shifting in device electroluminescence as well as in thin film photoluminescence. In field effect transistors, they also improve charge carrier mobility by an order of magnitude despite disrupting π-conjugation. This use of carborane-containing conjugated polymers in active devices holds promise as new responsive materials in electronic polymer applications.

Whilst the composition and arrangement of habitats within landscape mosaics are known to be important determinants of biodiversity patterns, the influence of seascape patterning and connectivity on temperate reef fish assemblages remains largely unknown. We examined how habitat patterns at multiple spatial scales (100–1000 m) explained the abundance and diversity of temperate reef fish in a reef-seagrass dominated seascape. Fish assemblages were surveyed using remote underwater videos deployed on 22 reefs in Jervis Bay, NSW, Australia. Using full-subset GAMMs, we investigated if habitat area, edge, structural connectivity and a metric for habitat diversity (Shannon’s diversity index) of reef and seagrass can predict variations in a temperate reef fish assemblage. A key finding of the study was that temperate reefs close ( 6.25 ha) seagrass meadows contained greater abundance and diversity of fish. A consistent negative correlation was also found between reef area (> 0.01 ha) and the fish assemblage. The influence of seascape metrics on the abundance of fishes varied with functional traits (trophic groups, mobility and habitat associations). Fish-seascape relationships occurred at a range of spatial scales with no single scale being solely important for structuring the fish assemblage. We demonstrate that it is important not to view reef habitats in isolation, rather consider a reefs context to adjacent seagrass when predicting the distribution of temperate reef fish. This finding improves current understanding of the multi-scale factors structuring temperate reef fish assemblages and highlights the importance of reef-seagrass connectivty for the management of temperate marine ecosystems.

Non-indigenous invaders may play ecologically similar roles to native species, and this may be reflected in the abundance, richness and composition of associated species assemblages. We investigated whether associations of epifauna with their macroalgal hosts differed between the non-indigenous Codium fragile ssp. fragile and native, congeneric C. fragile on three rocky shores in southeast Australia. Of the 38 taxa we recorded, 13 were unique to the native Codium and four to non-indigenous individuals. Holdfasts of non-indigenous Codium had double the taxon richness of epifauna compared to native holdfasts, and epifaunal abundances showed a similar but non-significant difference. Patterns of abundance and richness of epifaunal taxa on thalli of native and non-indigenous Codium varied depending on whether these measures were expressed per individual alga, thallus area or number of branches. The composition of epifaunal assemblages between native and non-indigenous Codium were significantly different, but differences among rocky shores were as great as those between macroalgal species. On all shores, two taxa, the gastropod Alaba opiniosa and gammarid amphipods, contributed most to compositional differences between native and non-indigenous Codium , and their abundances were influenced by branch number and associated epiphyte load. Host choice experiments manipulating the complexity and subspecies of Codium revealed that amphipods were more strongly influenced by branch number adjusted for epiphyte load than the identity of Codium. Our results highlight the importance of habitat features, such as structural complexity and associated epiphyte load, in determining whether native and non-indigenous species provide functionally equivalent habitats for associated assemblages.

The global marine environment has been impacted significantly by climate change. Ocean temperatures are rising, and the frequency, duration and intensity of marine heatwaves are increasing, particularly affecting coral reefs. Coral bleaching events are becoming more common, with less recovery time between events. Anomalous temperatures at the start of 2020 caused widespread bleaching across the Great Barrier Reef (GBR), extending to southern, previously less affected reefs such as One Tree Island. Here, nine video transects were conducted at One Tree Island, in the Capricorn Bunker Group, and analysed for community composition and diversity, and the extent of bleaching across taxa. Average live hard coral cover across the area was 11.62%, and almost half of this was identified as severely bleached. This bleaching event is concerning as it occurred in an area previously considered a potential refuge for corals and associated fauna from the risks of climate warming. Due to the global impacts of COVID-19 during 2020, this report provides one of potentially few monitoring efforts of coral bleaching. Supplementary information The online version contains supplementary material available at 10.1007/s10661-021-09330-5.

The present chapter explores the ritual times of ancient Israel. After providing a theoretical framework that draws on the work of Mircea Eliade, it provides an overview of the sacred times of the year in ancient Israel, as they are presented in the ritual calendars of the Hebrew Bible (e.g. Exod 23, 34; Lev 23; Num 28–29; Deut 16). Although this section follows the calendrical order of Israel festivals, it also considers how ritual times correspond to agricultural seasons and to the human life cycle. The final section highlights three features of sacred time in ancient Israel that can be drawn from the preceding overview.

Conflict between humans and large predators is a longstanding challenge that can present negative consequences for humans and wildlife. Sharks have a global distribution and are considered to pose a potential threat to humans; concurrently many shark species are themselves threatened. Developing strategies for coexistence between humans and this keystone group is imperative. We assess blimp surveillance as a technique to simply and effectively reduce shark encounters at ocean beaches and determine the social acceptance of this technique as compared to an established mitigation strategy—shark meshing. We demonstrate the suitability of blimps for risk mitigation, with detection probabilities of shark analogues by professional lifeguards of 0.93 in ideal swimming conditions. Social surveys indicate strong social acceptance of blimps and preference for non-lethal shark mitigation. We show that continuous aerial surveillance can provide a measurable reduction in risk from sharks, improving beach safety and facilitating coexistence between people and wildlife.

Millions of recreational boats and ~ 65,000 ocean-going merchant ships anchor routinely. Anchor and chain scour associated with these vessels mechanically disturb the seabed having implications for marine environments globally. Our review summarises the scientific literature that examines the response of biota to anchor scour across five habitats; unvegetated sediments; seagrass; rhodolith beds; coral and rocky reefs. Forty-one studies met our criteria with >85% of articles targeting recreational-based disturbances, mostly focussed on seagrass. Investigations of anchor scour from ships comes almost exclusively from cruise ships anchoring on coral reef. All research examined reported biota responding negatively to anchor scour, either directly or indirectly. Effects to biota were dependent on the spatio-temporal scale of the perturbation or the life-histories of the organisms impacted. We highlight several key knowledge gaps requiring urgent investigation and suggest a range of management strategies to work towards sustainable anchoring practices and the preservation of valuable seabed environments.

Objective To describe a new/modified technique to manage posterior vitreous pressure (PVP) during penetrating keratoplasty (PKP) and report a small series. Design Retrospective interventional case series and technique description. Participants PKP eyes necessitating mattress suture placement owing to PVP. Methods Retrospective chart review from 2016 to 2019 was undertaken. Placed prophylactically (before trephination) or after trephination, the mattress suture is placed limbus-to-limbus across the anterior chamber. A second mattress suture can be placed in the opposite meridian (perpendicularly) for added support (safety basket configuration). Variations of suture technique are described based on lens status (i.e., phakic, pseudophakic, aphakic) and intraoperative timing. Parameters assessed included demographics, lens status, suture indications, intraoperative technique details, successful PKP completion, and presence of primary failure. Results There were 6 phakic eyes (5 patients) and 9 pseudophakic/aphakic eyes (8 patients). Indications for the phakic subgroup were obesity (83%), poor scleral rigidity (83%), repeated iris prolapse (67%), dense mature cataract (33%), and planned large-diameter PKP (33%). Indications for pseudophakic/aphakic eyes included intraocular lens/iris prolapse (100%), pre-existing iris defects (67%), and planned large-diameter PKP (33%). Successful PKP was performed in all cases. Whereas one case had residual corneal edema in the setting of a persistent epithelial defect owing to limbal stem cell deficiency, all other cases demonstrated no primary graft failure. Conclusions Although increased PVP can present a stressful and challenging situation, it is important to have multiple options for management. This simple mattress suture technique normalizes the lens-iris complex behaviour and appears safe for the donor graft.

We thank Marie-Claire Demers, Rhiannon Kiggins, Mark Fackerell and Simon Rees for assistance with fieldwork. We acknowledge support from JBMP and Booderee National Park staff. We thank Geoff Hurt for assistance and construction of the BRUV units. We thank the 3 anonymous reviewers for their constructive comments. We also thank the Ecological Society of Australia and The Nature Conservancy, Australia, for project support.

Seagrass habitats worldwide are degrading and becoming fragmented, threatening the important ecosystem services they provide. Fauna associated with seagrasses, particularly cryptic species, are expected to respond to these changes, but are difficult to detect at ecologically meaningful scales using non-extractive techniques. We used a small, wide-angle camera (GoPro) and a small quantity of bait positioned within the canopy of Posidonia australis meadows in Jervis Bay, New South Wales to assess the response of fishes to seagrass cover. We saw a clear positive relationship with the condition of P. australis; a high cover of this seagrass had positive effects on the diversity and abundance of cryptic fauna. Our findings highlight ecosystem shifts associated with the loss and fragmentation of biogenic habitat. These changes are of particular relevance for P. australis meadows given their current status as an endangered ecological community in several locations in NSW and their slow rate of recovery from disturbance.

Este artículo contiene 8 páginas, 6 figuras., Sessile organisms are reliant on the use of refugia or chemical and physical defences to avoid or reduce attacks from predators. Many solitary ascidians possess a thick leathery outer tunic, sometimes reinforced with inorganic inclusions, that generally acts to deter predators. The genus Herdmania is remarkable among ascidians in possessing an abundance of barbed needle-like calcareous spicules in both the external tunic and the internal mantle. Our focus was on a habitat-forming subtidal ascidian – Herdmania grandis. We questioned why a large ascidian possessing a leathery test would possess spicules within the mantle – an apparent defence within a defence. We first quantified variation in spicule size and density within animals. Second, we examined the size and density of spicules for individuals of a range of sizes. Third, we incorporated these spicules at natural concentrations into feeding discs and tested their ability to deter gastropod predators that specialise in consuming ascidians and an asteroid that is considered a generalist consumer. Finally, we examined survivorship of lab-reared ascidian recruits when exposed to the starfish predator. Spicules constituted up to 30% dry weight (DW) of the tunic and an astounding 57% DW of the body wall (mantle). Spicules were significantly smaller in the contractile regions of the animal (the siphon and branchial basket) and were also found in lower densities, though not significantly. Mantle spicules were effective feeding deterrents; control feeding discs, lacking spicules, were consumed at three times the rate of discs with spicules (p < 0.05) by specialist ascidian predators, the Ranellid gastropods Cabestana spengleri and Ranella australasia. In contrast, we did not detect a significant difference in the consumption of feeding discs by the seastar Meridiastra calcar. In addition, the seastar reduced survivorship of 90 day old lab-reared recruits by four-fold. We contend that the primary defence mechanism of this ascidian is the leathery test and that this is effective against generalist consumers. The second line of defence – spicules in the mantle –is to thwart gastropod predators that bypass the tunic either by boring through it or by inserting their proboscis directly into soft tissues of their prey via the siphons. The presence of both a leathery tunic and spicules in H. grandis probably contributes to the dominance of this species on shallow subtidal reefs in southeastern Australia, where it is an important habitat-forming species. Our findings confirm the importance of considering a range of consumer strategies and life history stages in assessing potential control of engineering species by predation., We acknowledge financial support from the Centre for Sustainable Ecosystem Solutions, University of Wollongong. This work was completed while XT undertook sabbatical leave in Australia. Funding was provided by project CTM 2017-88080 from the Spanish Government. This represents contribution no. 318 from the Ecology and Genetics Group at UOW.

Adenoviral conjunctivitis comprises a large number of physician office visits in the United States and places a great financial burden on health care. It is estimated that the incidence of adenovirus infection to be as high as 20 million cases per year in the United States. There are multiple adenovirus serotypes, each associated with different types and severity of infection. Ocular manifestations of adenovirus include epidemic keratoconjunctivitis, pharyngoconjunctival fever, and nonspecific conjunctivitis. Adenoviral conjunctivitis is primarily a clinical diagnosis. Laboratory diagnosis is available although until recently rarely used. At present, there is no established or approved specific effective drug against adenovirus. Treatment is primarily supportive and includes artificial tears and cool compresses. Topical antibiotics are only indicated if a bacterial coinfection is suspected or in high-risk patients such as children. Prevention against this extremely contagious disease is of utmost importance. Although most cases are self-limited and have a relatively benign course, permanent visual disability can occur. For this reason, it is imperative that all eye care providers are capable of diagnosing and effectively treating these patients, and also preventing the spread of this contagious disease to others.

Seascape variability may confound assessments on the effectiveness of no-take marine reserves (NTMRs) in conserving biodiversity. In most cases baseline data are lacking, resulting in evaluations of NTMR effectiveness being Control Impact (CI) assessments. Even with independent replicate areas among management zones, this approach can make it difficult to detect zone effects if seascape attributes, such as habitat structural complexity varies among experimental areas. To determine the importance of structural complexity in evaluations of NTMR effectiveness we performed assessments on the abundance of a targeted fish, yellowtail kingfish (Seriola lalandi), in the Lord Howe Island Marine Park (LHIMP). We compared assessments which did and did not account for structural complexity, quantified using high resolution multibeam bathymetry. Despite almost 3 times more S. lalandi in NTMRs, the traditional CI assessment explained only 3% of the variation in the abundance of S. lalandi and revealed no clear effect of protection. Incorporating structural complexity into the assessment increased the deviance explained to 65% and uncovered an important interaction between zone and structural complexity. Greater abundances of S. lalandi were detected in NTMRs compared to fished zones but only on highly complex reefs. By accounting for structural complexity, we demonstrate that the precision and accuracy of NTMR assessments can be improved, leading to a better understanding of ecological change in response to this conservation strategy. Consequently, where marine park zones vary greatly in structural complexity, we strongly advocate for quantifying and accounting for such variability in assessments of NTMR performance.

An unnoticed parallel between Ezekiel 37:7 and a line from Esarhaddon’s Succession Treaty bolsters the claim that Ezekiel’s vision of dry bones was drawn from the Near Eastern treaty curse tradition.

Remote oceanic islands often display high levels of biodiversity and endemism, making them important locations for marine parks aimed at conserving biodiversity. To determine whether marine parks are reaching conservation objectives requires consistent assessments of their effectiveness through time. Lord Howe Island and Balls Pyramid are World Heritage listed remote oceanic islands in the Tasman Sea that support a diverse assemblage of fishes including many endemic and protected species. To conserve the region’s unique marine biodiversity, state and Commonwealth marine parks including no-take zones and partially protected zones open to line fishing were established. After approximately 5, 9 and 13 years of protection of shelf habitat we tested for changes in the marine park’s fish assemblage across management zones through time using baited remote underwater video systems (BRUVs). We detected no difference in total fish abundance, diversity, or assemblage composition between management zone types. The relative abundance of targeted carangids, yellowtail kingfish and silver trevally were 2 and 1.6 times greater in no-take zones than partially protected zones respectively, however, the substantial variation in their abundances among locations and sites meant that these differences were not statistically significant. No clear difference in the relative abundance of endemic, near-endemic and protected species were observed between management zone types. Generally, the abundance and diversity of fishes varied most among locations, sites and sampling years. The overall lack of difference in the fish assemblage between management zone types and its stability through time suggests current anthropogenic threats are relatively minor, and the marine park’s condition is reasonably healthy. Future surveys of the marine park’s fish assemblage will be valuable to test for body-size differences between zone types and to monitor trends in condition, particularly in response to possible changes in the number, frequency and intensity of anthropogenic threats.

Purpose To evaluate a region of interest (ROI) method of analyzing anterior segment optical coherence tomography (AS-OCT) corneal densitometry (CD) in the setting of Descemet membrane endothelial keratoplasty (DMEK) dehiscence. Methods Retrospective chart review of eyes that underwent (1) DMEK for Fuchs dystrophy (2) between 2018 to 2020 with (3) a partial DMEK dehiscence on AS-OCT, (4) involvement of only one side of the graft, (5) high-quality corneal AS-OCT scan, and (6) location of dehiscence within the central 5.5 mm of the cornea. Image analysis of the ROIs with ImageJ compared the total edematous area, mean stromal CD, and ratio of anterior-to-posterior (A/P) stromal CD for regions of DMEK dehiscence compared to the contralateral side with an attached DMEK graft. Control regions (with no dehiscence) and postdehiscence resolution images were also analyzed. Results Seventy sectors of the 21 images from 21 eyes with DMEK dehiscence were included. Compared to the contralateral side, regions of DMEK dehiscence had larger total areas (P < 0.0001), lower mean stromal CD (P = 0.0003), and higher A/P stromal CD (P < 0.0001). All control regions and postdehiscence resolution images did not show any significant differences compared to the contralateral sides. Conclusions This technique to analyze multiple ROIs on AS-OCT can be useful to evaluate CD of specific regions of corneal pathology. Lower mean stromal CD and higher A/P stromal CD may specify corneal edema. Translational Relevance Analyzing CD via multiple specific ROIs may be more suitable than measuring the CD of the full cornea and has broader applications extending to other corneal pathologies.

The development of environmental guidelines in the Antarctic and subantarctic is essential, because expansion of research, tourism, and fishing is placing these regions at increasing risk of contamination. Data are currently insufficient to create the region-specific guidelines needed for the unique conditions in these areas. To develop the most appropriate environmental guidelines, data from the most sensitive life stages of a species should be included to ensure effective protection throughout its life cycle. It is generally accepted that early life stages are more sensitive to contaminants. We compared the toxicity of copper between juvenile and adult life stages of 4 subantarctic marine invertebrates using sublethal and lethal endpoints. For 2 of the species tested, juveniles were more sensitive than adults. (The 7-d median effect concentration [EC50] values for the gastropod Laevilittorina caliginosa were 79 μg/L at the juvenile stage and 125 μg/L at the adult; for the flatworm Obrimoposthia ohlini, values were 190 μg/L at the juvenile stage and 300 μg/L at the adult.) For the isopod Limnoria stephenseni, juveniles were either more sensitive or of equal sensitivity to adults (7-d EC50 values: juvenile 278 μg/L and adult 320 μg/L). In contrast, for the bivalve Gaimardia trapesina, adults appeared to be more sensitive than young adults (7-d EC50 values: juvenile 23 μg/L and adult

Interspecific aggression is a critical determinant of the success and competitive superiority of many invasive over native species. While single abiotic stressors can alter aggression levels, the manner in which multiple stressors may alter the strength and outcome of interspecific interactions and hence the invasion potential of a species is still poorly understood, even though multiple stressors are prevalent in many ecosystems. Furthermore, multiple stressors may interact to produce synergistic or antagonistic effects on individual level behaviors, thereby modulating invasive-native species interactions in unexpected ways. Here we examined the effect of two key abiotic stressors in freshwater ecosystems-temperature and salinity-on interspecific aggression between the invasive eastern mosquito fish (Gambusia holbrooki) and juveniles of the native Australian bass (Macquaria novemaculeata). Under controlled laboratory conditions, individuals were exposed to low or high salinity levels (15 and 35‰), and low or high temperatures (21 and 28 °C), and the frequency of interspecific aggressive behaviors was scored. The effect of temperature and salinity on interspecific aggression was antagonistic for both M. novemaculeata and G. holbrooki. While elevated temperature promoted aggression, elevated salinity partially or entirely negated this effect. Moreover, regardless of temperature, M. novemaculeata was more aggressive than G. holbrooki under elevated salinity. In addition to this, the native displayed more aggression to smaller than larger heterospecifics when exposed to elevated salinity alone, while G. holbrooki showed no such preference. These results highlight the importance of considering the interplay between multiple abiotic stressors and behavioral interactions between invasive and native species, combined with the modulating effect of species-specific and size based responses to those stressors.

Dredging can have significant impacts on benthic marine organisms through mechanisms such as sedimentation and reduction in light availability as a result of increased suspension of sediments. Phototrophic marine organisms and those with limited mobility are particularly at risk from the effects of dredging. The potential impacts of dredging on benthic species depend on biological processes including feeding mechanism, mobility, life history characteristics (LHCs), stage of development and environmental conditions. Environmental windows (EWs) are a management technique in which dredging activities are permitted during specific periods throughout the year; avoiding periods of increased vulnerability for particular organisms in specific locations. In this review we identify these critical ecological processes for temperate and tropical marine benthic organisms; and examine if EWs could be used to mitigate dredging impacts using Western Australia (WA) as a case study. We examined LHCs for a range of marine taxa and identified, where possible, their vulnerability to dredging. Large gaps in knowledge exist for the timing of LHCs for major species of marine invertebrates, seagrasses and macroalgae, increasing uncertainty around their vulnerability to an increase in suspended sediments or light attenuation. We conclude that there is currently insufficient scientific basis to justify the adoption of generic EWs for dredging operations in WA for any group of organisms other than corals and possibly for temperate seagrasses. This is due to; 1) the temporal and spatial variation in the timing of known critical life history stages of different species; and 2) our current level of knowledge and understanding of the critical life history stages and characteristics for most taxa and for most areas being largely inadequate to justify any meaningful EW selection. As such, we suggest that EWs are only considered on a case-by-case basis to protect ecologically or economically important species for which sufficient location-specific information is available, with consideration of probable exposures associated with a given mode of dredging.