Mitigating fox predation on freshwater turtle nests: comparing effectiveness of three in situ protection methods

Mitigating fox predation on freshwater turtle nests: comparing effectiveness of three in situ protection methods | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL Ecology and Evolution This is a preprint and has not been peer reviewed. Data may be preliminary. 30 April 2025 V1 Latest version Share on Mitigating fox predation on freshwater turtle nests: comparing effectiveness of three in situ protection methods Authors : Christina Hunter , Deborah Bower , Richard Peters 0000-0002-5825-3591 , Ricky-John Spencer , Ligia Pizzatto do Prado , and James Van Dyke 0000-0002-3933-111X [email protected] Authors Info & Affiliations https://doi.org/10.22541/au.174599924.49036793/v1 Published Ecology and Evolution Version of record Peer review timeline 440 views 238 downloads Contents Abstract Supplementary Material Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract backend=biber, style=alphabetic, sorting=ynt ]biblatex Freshwater turtles in the Murray-Darling Basin (MDB), Australia, have declined since the 1970s. Intense nest predation by introduced foxes likely contributes to these declines, disrupting juvenile recruitment needed to sustain populations. Traditional lethal control methods, such as baiting and shooting, have proven inadequate, highlighting the need for innovative conservation strategies. We tested three nest protection methods—fenced nesting beaches, artificial floating islands, and individual mesh covers—for reducing fox predation. Using artificial turtle nests across protected and unprotected plots, we monitored nest destruction with remote cameras and confirmed nest status through excavation. On average, nest destruction was lowest on artificial islands (17%), followed by fences (37%) and mesh (40%). All protection methods significantly reduced predation compared to unprotected controls (85% destroyed). Unprotected nests were almost exclusively predated by foxes, while protected nests saw more predation from native animals. Native predator species did not differ among protection treatments. Our findings underscore the potential for artificial floating islands as a valuable conservation tool. Further research into optimizing nest protection and understanding ecological impacts is critical for improving recruitment and reversing declines. INTRODUCTION Nest predation is a significant threat to the reproductive success of many oviparous species and is a common cause of egg and juvenile mortality (Congdon et al., 1983; Menezes & Marini, 2017; Ricklefs, 1969; Schwanz et al., 2010). Introduced species increase nest predation beyond historic rates by thriving in new environments and exploiting native species which lack co-evolved defences against them (Banks & Dickman, 2007; Doherty et al., 2016; Fea et al., 2021). High mortality rates in young age classes is a significant problem for threatened species, as small population sizes, restricted distributions, and additional environmental pressures heighten their sensitivity to lost juvenile recruitment (Doherty et al., 2015; Webb et al., 2002). Developing effective, evidence-based methods to reduce nest predation is crucial to prevent current and predicted population declines driven by recruitment failure. Reducing nest predators typically involves lethal control methods like shooting and poison baiting (Doherty et al., 2015; Doherty & Ritchie, 2017; Saunders et al., 2010). While these methods may provide some short-term benefits (Christiansen & Gallaway, 1984; Fulton & Ford, 2001; Smith et al., 2010), they only reduce the number of predators (i.e., numerical response). Lethal controls do not account for the predator functional responses, which describe how the intake of an individual predator might change based on prey availability (Holling, 1959; Solomon, 1949). For highly efficient mammalian predators, such as raccoons ( Procyon lotor ) and foxes ( Vulpes vulpes ), predation rates by a small number of individuals can remain high despite large reductions in aggregate predator densities (Ratnaswamy et al., 1997; Spencer et al., 2017). To address the functional response, alternative nest protection methods are more effective by reducing predator access to nests using exclusion devices or barriers. For example, protective cages and guards on nest boxes have improved nesting success in numerous ground nesting and arboreal bird species (Gautschi et al., 2024; Stojanovic et al., 2019), and exclusion fencing has been used to create predator free havens for many threatened Australian mammal species (Legge et al., 2018). Turtles are a highly threatened vertebrate group often exposed to high nest predation rates over their extended incubation periods, offering a model system to study the effectiveness of various nest protection methods. Turtles are likely afforded some resilience to high egg and juvenile mortalities through their long lifespans, iteroparity and relatively high fecundity (Congdon et al., 1993; Mullin et al., 2023; Spencer & Thompson, 2005). However, extended periods of severely limited recruitment can jeopardize population stability and place turtle populations at greater risk of extinction as there is no replacement of older adults once they die (Lovich et al., 2018; Spencer, 2018; Spinks et al., 2003). In Australia, foxes are a major threat to turtles, with nest predation rates routinely exceeding 90% (Congdon et al., 1987; Terry et al., 2023; Thompson, 1983b). Some populations of two turtle species of Australia’s Murray-Darling Basin, Emydura macquarii and Chelodina longicollis , have experienced reductions of up to 69–91% since the 1970s; declines which were likely initiated by drought and exacerbated by heavy nest predation from invasive foxes (Chessman, 2011; Thompson, 1983b). Lethal methods are often ineffective for controlling foxes (Saunders et al., 2010), especially when targeting turtle protection (Robley et al., 2018). Thus, the development and testing of new methods is needed to effectively protect turtle nests and curb declines. Our study compares the effectiveness of three nest protection methods: wire mesh placed over individual nests, fenced nesting beaches, and artificial floating islands. Securing mesh grids over nests is a popular and inexpensive protection method that has successfully reduced nest predation in several turtle species (Bougie et al., 2020; Campbell et al., 2020; Lei & Booth, 2017; O’Connor et al., 2017; Yerli et al., 1997). Exclusion fencing is less widely used, but has effectively excluded foxes from western swamp turtle ( Pseudoemydura umbrina ) and western saw-shelled turtle ( Myuchelys bellii ) nests in Australia (Guyot & Kuchling, 1998; Streeting et al., 2023), and raccoons from map turtle ( Graptemys spp.) nests in the USA (Geller, 2012). Artificial floating islands have provided safe nesting habitat for numerous waterbird species (Hancock, 2000; McIntyre & Mathisen, 1977; Nakamura & Mueller, 2008), and when vegetated may additionally provide emerging hatchling turtles with food resources and refuge habitat in the root structures below, as seen in fish (Karstens et al., 2021; Nakamura & Mueller, 2008). Both the mesh grids and fenced nesting beaches are designed to physically block foxes, while artificial floating islands offer nest protection based on the assumption that foxes will not swim to reach them—an assumption that requires testing. While these protection measures may effectively exclude foxes, the impacts of native predators on turtle nests in the absence of invasives is not well understood. Turtle eggs are high in lipids and proteins (Booth, 2003), making them a sought-after resource for many native predators including monitor lizards ( Varanus spp. ) (Georges & Kennett, 1989), ravens ( Corvus spp .) (Baggiano, 2012), rakali ( Hydromys chrysogaster ) (Thompson, 1983b) and echidnas (Robinson et al., 2024). By removing competition from foxes, nest protection methods may inadvertently attract or concentrate native predators with similar capacities for nest destruction (Chessman, 2021), and ultimately fail to improve recruitment outcomes. Continued, long-term data are needed on novel nest protection methods to accurately evaluate their cost-effectiveness and determine the level of impact native predation may have under fox exclusion. Here we aimed to address the specific questions of 1) which nest protection method is most effective at preventing fox predation; and 2) does predator diversity differ between protection treatments? To address these questions, we created artificial nests and compared the rates of predation between unprotected nests and those protected by mesh, exclusion fencing and artificial floating islands. To compare predator diversities, we used remote camera footage to identify and quantify the predatory species responsible for each nest destruction event on both unprotected and protected nests. backend=biber, style=alphabetic, sorting=ynt ]biblatex STUDY AREA The field experiment was conducted at eight sites across north-central Victoria and south-eastern South Australia. These sites were a combination of disconnected, constructed reservoirs and natural wetlands connected to the broader Murray-Darling Basin. Sites were selected based on their relevance to active turtle nesting areas recorded on TurtleSAT (www.turtle sat.org.au). Field experiment Field research was conducted after the peak laying period of the two focal species ( Emydura macquarii and Chelodina longicollis ) to prevent attracting additional foxes to incubating turtle nests and disrupting nesting females. Artificial nest plots were carefully situated to avoid turtle nests mapped in TurtleSAT whilst remaining within ~100 m of nesting locations. Artificial nest plots were placed within similar soils as real nests to mimic turtle preferences at a given site, which included a range of hard, soft and sandy soils all within ~200 m of the water’s edge (Kennett et al., 2009; Petrov et al., 2018; Spencer & Thompson, 2003). Nest plots were created between December 2023 and January 2024 and buried over a 3-month period to resemble an average between the typical incubation periods of E. macquarii and C. longicollis (Kennett et al., 2009; Spencer, 2002). At the end of the study period, the number of destroyed nests in a plot was determined through a combination of visual surveys, excavation of nests with a hand trowel and inspection of remote camera images. backend=biber, style=alphabetic, sorting=ynt ]biblatex Plot creation Mesh Mesh protection was used on the banks of two wetlands in northern Victoria, Aus., and involved covering each nest in a plot with a 50 cm x 50 cm square of wire chicken netting (50 mm aperture) held in place by eight tent pegs at each corner and side. At the larger wetland, two meshed plots were created alongside two corresponding control plots created within 100 m of the treatment plot. At the second, smaller wetland, only one treatment and one control plot were created. Artificial nest plots measured 10 m x 5 m within the mesh treatments, with wooden stakes set at each corner of the plot. To capture the types of predators and date/time of nest raiding, one corner stake was fitted with an infrared remote camera (Campark T85) which was orientated downward and in a direction that minimized glare. The camera was also aimed to ensure that its field of view captured every nest in the plot. Ten nest holes were dug to 150 – 200 mm deep (following Terry et al., 2023) using an electric drill and auger, and were placed haphazardly within the plot. Chicken eggs were used to eliminate the sacrifice of turtle eggs, with two eggs in each nest hole representing an intermediate between the average mass of an E. macquarii and C. longicollis clutch (Kennett et al., 2009; Spencer & Thompson, 2005; Thompson, 1983a). Once buried, marker flags were positioned on nests and photos were taken at each corner of the plot to allow for nests to be later located by estimating their distance from the corner stakes and adjacent nests. All marker flags and non-camera stakes were then removed. Fence Nests that were protected by fencing had 1 – 2 plots created inside four separate fenced areas. The fenced areas were purpose-built to protect known turtle nesting areas between 2016 and 2023. Each fence was constructed primarily of Cyclone TM or generic anti-predator fencing at least 2 m tall, with 0.5 m of skirting on the ground. The aperture of the fence mesh was 4 cm diameter at most. The fence enclosed areas of varying sizes on three sides, where the fourth side was always open to an adjacent wetland. The wetland-ends of the fencing extended into the wetland at least 3 m at all locations to prevent wildlife from easily walking around the ends of the fence and into the enclosed area. This arrangement allows turtles to access the fenced area from the wetland, but prevents any direct land access. The smallest fenced site (n=1) was only large enough to construct one plot inside the fence, while the remaining larger fenced sites (n=3) had two. An equal number of control plots were also created outside the fence, within 100 m from the protected nests. All nest plots were created identically to those used in the mesh treatment. Island Artificial floating islands (hereby AFIs) were depolyed at two sites. One site had only one AFI, while the larger remaining site had two AFIs anchored ~50 m apart. Plot construction was modified under the island treatment to accommodate for the size limitations of the AFIs. The floating islands were comprised of a 5 m x 3 m steel mesh platform supported by eight 150 mm diameter PCV tubes, sealed at both ends to ensure buoyancy. Two nesting boxes, each measuring 650 mm x 400 mm, were placed on top of the steel platform and filled with soil. Steel mesh frames wrapped in hessian jute were attached to the sides of nesting tubs to create turtle access ramps, and coconut fibre was wrapped across all remaining exposed mesh. AFIs were deployed by kayaks and anchored using sand anchors and 5 mm marine-grade stainless steel cable. Using the same protocol as above, four articial nests were created on each of the 3 AFIs (two nests per nesting box), with remote cameras places on opposite ends of the nesting tubs to capture predation events. To match the smaller size of the island plots, 5 m x 2.5 m control plots with five nests per plot were created on the nearest shore. backend=biber, style=alphabetic, sorting=ynt ]biblatex Statistical Analysis Nest protection We conducted all statistical analyses in the R statistical environment (v4.3.3; R Core Team 2021). To analyse the relationship between the nest protection treatment and the proportion of destroyed nests while accounting for variation between locations, we employed a Generalised Linear Mixed Model (GLMM) to model logistic regressions. The GLMM was fitted using the ‘glmmTMB’ function from the ‘glmmTMB’ package (Brooks et al., 2017). The GLMM compared the number of detroyed nests per plot out of the total number of nests within the plot as the response variable. The treatments (mesh, island, fence, control) were incorporated as categorical fixed effects, and the location of plots (out of eight potential sites) as a categorical random effect to account for potential correlation and variability within and across locations. The model was fitted with a binomial family and logit link function. Estimated marginal means were obtained using the ‘emmeans’ function in the ‘emmeans’ package (Lenth, 2024). To assess the significance of the fixed effects (treatment), we performed Type III tests using the ‘anova’ function. Type III tests determine the significance of each treatment effect on nest destruction rates, while accounting for the other factors in the model. Pairwise comparisons were then performed with Tukey adjustment to account for multiple testing. Predator types To compare the types of predators raiding nests across protected and control plots we used Non-metric Multidimensional Scaling (NMDS) using the ‘vegan’ and ‘dplyr’ packages in R (Oksanen et al., 2023; Wickham et al., 2023). Data was obtained from camera images, which recorded the predator responsible for every predation event within each plot. NMDS analysis allows for the similarity or difference in predator composition to be visualised across treatment and control groups. The NMDS was created using the ‘metaMDS’ function with a Euclidean distance. Differences in predator types between protection treatments and control groups were statistically tested using a PERMANOVA on the Euclidean distance matrix, which was based on the proportions of nest destruction attributed to each predator. We then performed pairwise comparisons using the ‘pairwiseAdonis’ function to identify specific differences between treatment and control groups. backend=biber, style=alphabetic, sorting=ynt ]biblatex RESULTS Nest protection On average, the control plots had the highest percentage of destroyed nests, with nest destruction occuring at more than twice the rate of mesh and fence-protected nests and five times the rate of nests on islands (Fig. 1). The GLMM analysis showed that nest destruction rates differed across the treatments (F 3, 15 = 19.16, P < 0.05). The mesh, fence, and island treatments all experienced less nest predation compared to the control, but there were no significant differences in destruction rates between the protection treatments (Fig. 1, Table 1). backend=biber, style=alphabetic, sorting=ynt ]biblatex Predator types Foxes were the dominant predator across all control plots and were responsible for 93% of all destroyed nests in this group (Table 2). Fox predation was also high in the meshed plots, comprising 83% of the total destroyed nests, while raven ( Corvus coronoides ) predation accounted for 69% of the nests destroyed at fenced sites. Only 17% of nests were damaged on islands, and these were entirely attributable to Australasian swamphens ( Porphyrio melanotus ).NMDS plots of predator species display all three protection treatment centroids (centroids indicated by asterisks) clustered in the top and bottom left quadrants, while the control centroid is placed to the right of the central intersection (Fig. 2A). Predator species of the control plots differed significantly from those seen in each protection treatment group, however, there were no significant differences in nest predator species between each of the protection treatment groups (PERMANOVA, Table 3). This difference is primarily because foxes were the main predators in the control nests, but were substantially reduced by all the nest protection methods. As the control group was dominated by foxes as the primary predators, the NMDS analysis was run again with the control group excluded to determine whether any differences in nest predators occurred only within protection treatments. After excluding the control group and plotting the NMDS only for nest protection treatments (Fig. 2B), the mesh and island centroids are both placed within the 85% confidence ellipsis of the fence group, illustrating no significant difference from one another (Table 3). Both island and mesh groups shared predators with the fence group, but not with each other (Table 2). Thus, there was no evidence that nest protection method substantially affected the diversity of predators capable of attacking the nests, once foxes were excluded. DISCUSSION Mesh screening, exclusion fencing, and artificial floating islands all effectively reduced fox predation on artificial nests, demonstrating that using any of these methods provides greater protection than leaving nests unprotected. We demonstrate here, for the first time, that artificial floating islands offer a uniquely secure nesting site. The islands provided the only protection strategy that foxes did not breach. Foxes destroyed 90–100% of nests in control plots, which aligns with previous observations of similarly high predation rates of unprotected nests (Congdon et al., 1987; Munscher et al., 2012; Purger et al., 2023; Terry et al., 2023; Thompson, 1983b). Once excluded, however, we were able to test whether native predators replaced the predation pressure of foxes in the presence of our exclusion methods. Determining historic native predation rates before the introduction of foxes is challenging due to a lack of historical data, and it is conceivable that when foxes are excluded native predators will destroy nests with similar frequency (Chessman, 2021). In our study, native predators did raid nests following the exclusion of foxes, however, predation rates were significantly lower in protected plots than in control plots. If native predators were to directly replace foxes, then we would expect consistent predation rates across all groups. In particular, birds are easily able to access the floating islands and fenced nesting beaches (Fig. 3), and so should not be excluded by those nest protection methods. Here, the lower predation rates in protected plots suggest that native predators are not as impactful as foxes in terms of nest predation when foxes are no longer present, and that the protection methods may also reduce predation by native predators. backend=biber, style=alphabetic, sorting=ynt ]biblatex Islands Artificial floating islands were the best-performing protection method, but their placement may influence the level of protection that they provide for nesting animals. Two nests on islands were exposed at the conclusion of the study, which from camera footage looked to be brought to the surface by digging native Australasian swamphens ( P. melanotus ). These birds had previously destroyed nests in other locations, indicating they will likely continue to pose a threat to nest survival on all islands. Importantly, no foxes reached any floating islands, which likely reflects an aversion to swimming. Although foxes may swim to food sources or to escape danger (Angerbjörn, 1989; Murie, 1959), the swimming distance required to access floating islands may serve as a sufficient disincentive for foxes, although this could depend on the availability of food on the shore. Given their excellent sense of smell and visual acuity (Lai et al., 2015; Petrov et al., 2018), it is possible that foxes are capable of smelling nests or spotting nesting females on floating islands within several meters of the shore, and therefore, islands should be anchored well away from the shore where possible. Floating islands can be costly to construct (typically ranging from AU$5,000–$10,000), but require little ongoing maintenance (aside from the annual preparation of nesting boxes) once deployed. For successful incubation on floating islands, the soil composition and drainage capacity of nesting boxes should be tailored around the optimum temperature and moisture conditions of the target turtle species (Wilson, 1998). If incubation requirements are not known, these data should be gathered first to avoid unnecessary egg mortality through failed incubation. Fence Fox predation was minimal accoss our fenced sites, supporting the use of fences as an effective barrier against foxes (Guyot & Kuchling, 1998; Streeting et al., 2023). Native predation was also generally low, however, this varied across sites. Ravens ( C. coronoides ) were particularly active nest predators at one site, destroying 90% of all nests inside the fence. Ravens are predators of a broad range of turtle eggs and hatchlings (Boarman, 2003; Ercolano, 2008; Thompson, 1983b), and typically destroyed nests in our study in groups of three animals (Fig. 3). Social learning through observation of conspecifics is well recorded in corvids (Bugnyar & Kotrschal, 2002; Emery & Clayton, 2004; Midford et al., 2000), and this could, in part, explain the rapid group-raiding of nests at this site. The absence of raven predation at other fenced sites might stem from an unfamiliarity with turtle eggs as a food source. Once discovered, this may lead to a significant increase in nest predation, as seen in feral pigs ( Sus scofra ) (Engeman et al., 2016). Unlike in open systems, eradication of pest predators is feasible inside fenced areas (Legge et al., 2018), and prior to creating artificial nests plots there were no fox dens identified within any fenced sites used in our study. However, a fox did enter a fenced site on one occasion when lowering water levels caused by a short drought likely allowed it to walk around around the edge of the fence and destroy 50% of nests inside. In future, fox incursions could be avoided by extending end posts of the fence far enough into the water to ensure the area remains enclosed even during dry periods (Streeting et al., 2023). Even with this deterrent, however, foxes may swim in around the outskirts of fenced sites (Dickman, 2011). Similar to floating islands, fenced nesting sites require little ongoing labour aside from occassional maintenance. However, their construction can entail reasonably high upfront costs and may disturb or alter nesting habitat, potentially affecting the liklihood of turtles nesting there. While we did not observe any turtles trapped in the fences used in our study, fencing may pose a risk to dispersing females (Ferronato et al., 2014), and require alterations; see (Dowling et al., 2024; Guyot & Kuchling, 1998; Waltham et al., 2022). Further research on the value of fenced nesting sites in relation to real turtle nesting behaviour would benefit future management decisions. Mesh While better than no protection at all, mesh was the poorest performing protection treatment, and experienced average predation rates (40%) similar to those seen in other studies using mesh to deter turtle nest predators (Nordberg et al., 2019; O’Connor et al., 2017; Terry, 2024). Foxes can break into nests by pushing their snouts or paws throuh through the holes in the wire (Fig. 4), and while a finer aperture wire may prevent this, it would not allow for hatchling turtles to pass through when emerging from the nest. The risk of predators breaking through the mesh is most likely determined by the type of material used in relation to the types of predators being controlled for (Lovemore et al., 2020; Pheasey et al., 2018). For instance, plastic mesh may be sufficient to protect nests from dingoes ( Canis familiaris ) (Nordberg et al., 2019), monitor lizards ( Varanus panoptes ) (Lei & Booth, 2017) and coyotes ( Canis latrans ) (Lovemore et al., 2020), but may be less effective against foxes. When used against foxes, predation rates of up to 100% have occurred using plastic mesh as it can be easily chewed through and broken, even when multiple layers are used (Terry et al., 2023). Similarly, wire cages can afford sufficient protection from foxes and raccoons (Procyon lotor ) (Kurz et al., 2012; Streeting et al., 2023), but not feral pigs ( S. scofra ) (Engeman et al., 2016). For predators that primarily hunt using olfactory cues, such as foxes, it is unlikely that the visual presence of protective mesh alone increases predation rates over time through an association with food (Bowen & Janzen, 2005; Jobe et al., 2023; Terry, 2024). However, other predators using a combination of visual, tactile and olfactory cues may learn to associate mesh with food, thereby focusing their predation efforts on these markers (Bougie et al., 2020; Mroziak et al., 2000; Rollinson & Brooks, 2007; Schindler et al., 2017; Williams et al., 2020). Covering mesh with a fine layer of sand or soil may be a simple way to reduce visibility to predators (Kurz et al., 2012; O’Connor et al., 2017). While mesh may not be a visual cue for foxes, its use will likely have diminishing returns if break throughs are left unchecked and concerted efforts by foxes consistently result in a food reward (Niehaus et al., 2004). Quickly replacing broken mesh (or other exclusion devices) with sturdier alternatives can modify fox behavior, leading them to ignore protected nests once they learn they cannot break through (O’Connor et al., 2017). In corvids, 85% of predation events ended within two minutes when birds failed to access nests through exclusion cages (Major et al., 2015). A final limitation in using mesh as a protection method is the need to find intact turtle nests, which can be incredibly cryptic (Ratnaswamy et al., 1997; Terry et al., 2023; Wirsing et al., 2012). The in-person hours required to find nests can be expensive if this is paid time (Ratnaswamy et al., 1997) and subsequently, many projects rely on volunteers (O’Connor et al., 2017; Riley & Litzgus, 2013) or additional cues such as trail cameras or scent detection dogs (Streeting et al., 2023). Management implications While artificial floating islands are a novel conservation method for freshwater turtles, our findings support their continued use and further research into their potential benefits and optimized design. Both artificial floating islands and exclusion fencing provide scalable, long-term nest protection solutions, but require significant initial investments and resource commitments. Mesh protection is labor-intensive due to the effort required to locate nests, but it is likely a more cost-effective option for protecting individual nests since the materials required are inexpensive (less than $1 AUD per nest). However, in high-risk areas, mesh may require reinforcement with exclusion cages or rigid wire to effectively prevent predator access. In conjunction with monitoring nest destruction rates, further monitoring of nesting preferences in female turtles and the survival of resulting hatchlings is needed to accurately assess the cost-benefit and practical effectiveness of floating islands, fences and mesh as conservation strategies. REFERENCES Angerbjörn, A. (1989). Mountain hare populations on islands: effects of predation by red fox. Oecologia , 81 , 335-340. Baggiano, O. (2012). 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Collection Ecology and Evolution Keywords ecological experiment freshwater population ecology terrestrial vertebrate Authors Affiliations Christina Hunter La Trobe University View all articles by this author Deborah Bower University of New England View all articles by this author Richard Peters 0000-0002-5825-3591 La Trobe University View all articles by this author Ricky-John Spencer Western Sydney University View all articles by this author Ligia Pizzatto do Prado La Trobe University View all articles by this author James Van Dyke 0000-0002-3933-111X [email protected] La Trobe University View all articles by this author Metrics & Citations Metrics Article Usage 440 views 238 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Christina Hunter, Deborah Bower, Richard Peters, et al. Mitigating fox predation on freshwater turtle nests: comparing effectiveness of three in situ protection methods. Authorea . 30 April 2025. 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