North Central Catchment Management Authority

Abstract Marine protected areas (MPAs) are important conservation tools, however, efficacy can, in part, be a function of their size in relation to the home range of the target species. The eastern blue groper, Achoerodus viridis , is a long‐lived, protogynous hermaphrodite, and an ‘iconic’ marine species in eastern Australia, with several MPAs having been established specifically for their protection. Site fidelity, habitat use, and home range size were assessed for 29 adult eastern blue gropers monitored for up to 374 days using passive acoustic telemetry within and around a small marine reserve. The fish exhibited long residency times and no movement was recorded between adjacent reefs, suggesting sand acts as a natural barrier to movement. Core ranges were calculated using 50% kernel utilization distributions (KUD) and estimated between 0.005 and 0.092 km 2 . Males had larger core ranges than females or fish of indeterminate sex. There was no statistical difference between the breeding/non‐breeding seasons. Home ranges were calculated using 95% KUD and ranged between 0.03 and 0.54 km 2 . Home range size was largest for males and significantly larger for all sexes in the breeding season. Fish tagged in the ‘no‐take’ area of the MPA had smaller home ranges than fish tagged in the area where fishing is permitted. This study indicates that even relatively small MPAs can provide effective protection for adult eastern blue groper, supporting the proposition that large reef dwellers with long residency times can be used as flagship species to gain public support for the designation of MPAs. Copyright © 2014 John Wiley & Sons, Ltd.

A survey of intertidal habitats, including coastal rock pools, was undertaken across New South Wales (NSW), Australia, February to May 2012, to test the hypothesis that the distribution and abundance of threatened juvenile black cod Epinephelus daemelii (Günther, 1876) does not differ across marine bioregions. An assessment was also provided on their habitat use and site fidelity. Various methods were trialled to determine the best method for detecting juvenile E. daemelii, with the most suitable method being the deployment of small baited underwater high definition video cameras for a period of 30 min. Using these baited video cameras, sampling occurred across four bioregions in NSW, covering approximately 800 km of coastline. Within each bioregion, a minimum of nine locations was selected, and at each location a minimum of six intertidal habitats was surveyed for the presence of E. daemelii. Of 412 sites surveyed, a total of 20 juveniles (mean size = 16.7 cm ± 1.1 cm SE) were found in intertidal habitats along approx. 420 km of coastline. The smallest juvenile was LT 3 cm and the largest fish was stereo measured at LT 26.5 cm. E. daemelii were found to tolerate a large range of water quality parameters, particularly temperature (mean 21.7°C ± 0.7 SE, min = 16.8°C and max = 31.2°C) and dissolved oxygen (mean 11.2 mg L−1 ± 1.3 SE, min = 5.7 mg L−1 and max = 19.2 mg L−1). E. daemelii were found in habitats dominated by boulders and overhangs, indicating a preference for structural features that provide solid cover. No E. daemelii were recorded at sites that had algae as the dominant habitat type. Juvenile E. daemelii were found to display site fidelity to rock pool habitats, with two individuals recorded as remaining at their same sites for a period of 471 days, even though the rock pools were open to the ocean at high tides. This study indicates that the abundance of juvenile E. daemelii is low, especially north of Port Stephens where adults are most abundant. Use of the small baited video cameras proved to be a successful sampling method to confirm that juvenile E. daemelii utilise rock pool and shallow reef intertidal habitats in the early stages of their life cycle.

Context A framework was developed to help investors improve the delivery of environmental benefits from environmental programs. The framework, Investment Framework for Environmental Resources (INFFER), assists environmental managers to design projects, select delivery mechanisms and rank competing projects on the basis of benefits and costs. Aims To identify design requirements for an environmental investment framework on the basis of consideration of lessons from practical experience, and established theory from decision analysis and economics. Methods The design and delivery of the framework are based on extensive experience from working with environmental managers and policy makers. In addition, the developers have paid close attention to the need for processes that are theoretically rigorous, resulting in a tool that allows valid comparison of projects for different asset types, of different scales and durations. Key results From the practical experience outlined, several important lessons and implications are identified, including the need for simplicity, training and support of users, trusting relationships with users, transparency, flexibility, compatibility with the needs and contexts of users, and supportive institutional arrangements. Use of a theoretically correct metric to rank projects can deliver dramatically improved environmental values relative to a commonly used weighted additive metric. Conclusions Practical and theoretical considerations have strong implications for the design of a practical, effective and accurate tool to support decision making about environmental project priorities.

Accurate estimation of climate change impacts on catchment hydrology is essential for effective future water management. The efficacy of such estimations is dependent on proper climate model selection. In this study, an attempt was made to formulate a methodology for climate model selection, evaluating eight climate models from the sixth phase of the Coupled Model Intercomparison Project (CMIP6). The models were assessed for their ability to simulate variables used in hydrological studies and large-scale atmospheric circulation influencing rainfall in Australia. Five statistical indicators Root Mean Square Error (RMSE), Spatial Correlation (SC), Percentage Bias (Pbias), Normalized Root Mean Square Error (NRMSE), and Nash-Sutcliffe Efficiency (NSE) were used to evaluate the performance, and the models were ranked through Compromise Programming (CP), a multiple criteria decision making technique. Results show that HadGEM3-GC31-LL performed well in most of the categories considered and was top top-ranked model overall followed by GFDL-ESM4, CESM2-CAM6-RT, and CanESM5 for Australia. Conversely, MIROC6 consistently ranked lower in most of the categories. In the context of simulating hydrological variables, CESM2-CAM6-RT, HadGEM3-GC31-LL, and GFDL-ESM4 emerged as the top three models. The robustness of the proposed methodology suggests its applicability for model selection, making it a replicable approach for climate change impact assessment studies in diverse regions.

Lifestyle landowners value land for its amenities and ecological characteristics and could play an important role in managing and conserving native vegetation in multifunctional rural landscapes. We quantify values of ecosystem services captured by owners of rural lifestyle properties in Victoria, Australia, using a spatial hedonic property price model. The value of ecosystem services provided by native vegetation is maximized when that vegetation occupies about 40 percent of the area of a lifestyle property. Since the current median proportion of native vegetation is 15 percent, most lifestyle landowners could benefit from increasing the area of native vegetation on their properties.

Worldwide, riverine fish are the target of environmental water because populations have declined in lotic river habitats following river regulation. Murray cod is an endangered Australian riverine fish with remaining populations associated with lotic river reaches with instream habitat, including some creeks operated as part of irrigation systems. Our objectives were to develop a life history model, apply the building block method of environmental flows to enhance the abundance of juvenile Murray cod and promote population recovery. From 2008 to 2018 we evaluated changes to Murray cod juvenile abundance before and after implementation of a perennial environmental flow regime that began in 2013. During the first year of the environmental flow, larvae were collected as evidence of spawning. Murray cod abundance can be enhanced with environmental flows that target: (1) an annual spring spawning or recruitment flow with no rapid water level drops; (2) maximising hydrodynamic complexity (i.e. flowing habitats that are longitudinally continuous and hydrodynamically complex); and (3) an annual base winter connection flow. Recognition that incorporating hydraulics (water level and velocity) at fine and coarse time scales, over spatial scales that reflect life histories, provides broader opportunities to expand the scope of environmental flows to help restore imperilled fish species in regulated ecosystems.

Natural resource management organisations in Australia routinely establish resource condition targets in their regional plans and catchment strategies. We reviewed biodiversity, water and community resource condition targets set by Catchment Management Authorities (CMAs) in Victoria and New South Wales (NSW) over planning cycles since 1997 against criteria of being specific, measurable and time-bound (SMT). The overall quality of targets is poor, with less than 30 per cent of targets meeting the three criteria. Disturbingly, there are no SMT targets in the most recent NSW CMA catchment strategies. We identify three major reasons for poor target setting: a lack of appropriate standards and guidelines from governments to enable high quality target setting; a lack of realism about the budgetary and technical feasibility of ambitious environmental targets amongst those involved in natural resource management; and a lack of adequate focus on outcomes by both CMAs and governments. Improvements to target setting can be achieved through stronger signals and commitment by governments, including by rewarding performance of regional bodies practising outcome-focused accountability.

Groundwater resources have deteriorated in many regions as a result of excessive use to satisfy increasing water demands. Furthermore, climate change has an influence on groundwater in terms of quality and quantity. An investigation of climate change impacts on quality and quantity of groundwater is vital for effective planning and sustainable management of groundwater resources. Despite of the importance of climate change impact studies on groundwater resources, climate change impact studies related to surface water resources have attracted more attention from the research community, leading to limited understanding of the groundwater and climate change relationship. In this paper, a systematic review of the latest literature related to the impact of climate change on groundwater recharge was carried out to provide guidance for future studies.

Plans to provide water to floodplain ecosystems are frequently constrained by insufficient ecological and hydrological data. Published ecological studies provide a range of indicator species to assess the impacts and to predict the responses of water management. However, if the a site’s hydrology and ecology is not well known, this information is of little value.This paper presents an approach to apply the known responses of indicator species to an ecosystem where the hydrology is poorly understood. Gunbower Forest, a River Murray floodplain ecosystem in northern Victoria, has experienced reduced flooding as a consequence of river regulation and diversions. This project assessed the ecological impacts of hydrological change and recommended compensatory water provisions.Foresters had previously mapped the spatial distribution of timber quality classes in Gunbower Forest. The known relationship between timber quality and flooding at Barmah Forest was applied to Gunbower Forest to map hydrological classes. The flora and fauna associated with these classes were attributed from known hydrological relationships at Barmah Forest and the wider scientific literature.A key finding of the project was that low flows are important in rehabilitating permanent wetlands in the forest. The current framework for providing environmental flows is inadequate in this respect. Floodplain ecosystems are generally provided with large, infrequent flows from allocations of surplus flows. However, small, frequent inflows require allocations of secure water which are not widely available to the environment.

Abstract Collaborative approaches to conservation management are critical to respond to the ongoing biodiversity crisis. However, local community involvement in many conservation actions is lacking, especially within translocation and reintroduction programs. Similarly, rapid integration of genetic information into collaborative programs with local communities is rarely conducted. Here, we describe a community‐based and collaborative reintroduction program for a threatened Australian freshwater fish, the southern pygmy perch ( Nannoperca australis ). We integrate on‐the‐ground translocation efforts by volunteers from local communities, captive breeding by a private aquarium business, and genetic analyses done by a research institution to provide a holistic framework for the reintroduction of southern pygmy perch. We evaluated genetic diversity, population structure, relatedness, and inbreeding across the duration of the reintroduction program using data from neutral and adaptive genomic markers. This allowed us to assess the ability of such a program to minimize inbreeding and retain genomic variation, and to promote adaptive potential of the reintroduced population. While genetic variation for the source populations was very low, we found no decrease in genetic diversity or increase in inbreeding across the program. These genetic findings support the efforts made by local communities and will further inform future reintroductions as part of a collaborative conservation framework. We expand on our empirical case study by describing a theoretical framework for integrating conservation genomics research with community‐led conservation management programs and identifying the benefits of such a collaboration. Our study highlights the importance of multifaceted and integrated conservation management approaches to effectively protect and manage threatened species.

Monitoring is an essential part of an environmental management system (EMS) if landholders are to demonstrate improved environmental performance. This paper reports results of two surveys to determine environmental issues and priorities for monitoring. The first survey was conducted on 12 EMS pilot projects, and the second on 18 catchment management organisations in Australia. With the exception of pastoral zones, EMS facilitators identified moderate to major issues in land condition, water balance, riparian zone, native vegetation condition and pests. Water quality issues were rated as minor to moderate problems. Issues raised by the greatest number of respondents were water balance problems and weed and pest issues. Catchment managers reported widespread degradation issues in land condition, water balance problems, altered water flow, water quantity and availability and water quality. Degradation of the riparian zone and native vegetation were also reported. Both EMS facilitators and catchment management organisations understood the need for environmental monitoring; however, few EMS pilot projects have addressed it. This was due, in part, to a lack of readily available tools and concentration on the EMS process itself. Tools of most interest to facilitators were soil erosion risk, soil test interpretation, soil structure assessment, soil health, water leakage and perenniality, water quality, riparian zone management, herbicide resistance, greenhouse emissions and energy use. Facilitators also suggested that tools should be delivered in several formats, but workshops delivered by experts were of most interest. Catchment managers had realistic and pragmatic views about the role of landholder monitoring in assessing catchment outcomes and there is a mismatch between landholder monitoring and catchment reporting requirements. Landholders are likely to monitor only what is in their direct interests and this will be mainly on land condition. We conclude that on-farm environmental monitoring conducted by landholders will be of limited use for catchment management organisation reporting. However, it will be very important in helping farmers to make more informed decisions about their environmental management, together with education and support. The issue of catchment condition monitoring and reporting requires serious attention as current monitoring and reporting is likely to be inadequate.

Abstract The hydrological variability of intermittent streams means that the spatial distribution of dry‐season aquatic refuges within river networks and the temporal dynamics of hydrological connectivity between them are critical for the persistence of aquatic biodiversity. Here, a new approach is demonstrated to identify surface water bodies as priority refuges for efficient conservation management of freshwater biodiversity in intermittent stream networks. Recently developed models of surface water extent and daily streamflow were used to represent spatio‐temporal variations in hydrological connectivity and surface water persistence within river networks of eastern Australia over a 107‐yr period. Using this information, systematic conservation planning was applied to prioritize aquatic areas for conservation of 25 fish species under two scenarios. One scenario identified priority refuges to complement those already occurring in protected areas, whereas the other did not consider protected area status. The priority networks identified concentrated on the main stems of river catchments where surface water was more likely to be persistent and aquatic refuges were more likely to be connected, but also included headwaters for rare fish species. All three set conservation targets for the 25 fish species can be met in the best solution of priority networks. Although the second scenario achieved the targets with a smaller size of priority network overall, it required more new aquatic refuges and was thus less efficient than the first scenario. The newly developed datasets are useful for freshwater conservation prioritization because they account for hydrological variability of intermittent streams. The systematic prioritization approach applied is transferable to other regions and freshwater taxa to identify aquatic refuges for biodiversity conservation within intermittent stream systems.

Context Where conservation efforts are undertaken to decrease downward trends in fish populations, comparatively few resources are directed to small-bodied cryptic species. The true extent of the decline of many of these species is therefore often unknown. Where surveys have occurred, they are frequently limited by budget and hence effort. Consequently, there is a risk that rare species may not be physically captured despite their presence at a site. Such an outcome has dire consequences for the conservation of remnant populations of threatened fish. To counter possible false negative detections, environmental DNA is increasingly being used in conjunction with, or as a precursor to, physical surveys. The Southern Purple-spotted Gudgeon (Mogurnda adspersa) is a small, threatened freshwater fish native to Australia. Recent surveys captured M. adspersa in two highly turbid waterbodies in north-central Victoria. This capture represented the first detection of the species in the state in more than 20 years. Because these waterbodies are part of a network of hydrologically connected systems, it was suspected that the species likely had a broader distribution in the region. Aims To develop a probe-based eDNA assay for M. adspersa and compare its sensitivity against a physical sampling program. Methods Detection (presence/absence) between eDNA and traditional surveys was compared across multiple sites. Key results eDNA presents an effective tool for determining the presence of M. adspersa. The eDNA survey demonstrated significant clustering of eDNA detections towards the outlets of lakes sampled, suggesting concentrated eDNA at this point, or that, due to the channels being shallower, the eDNA of resident individuals may be less diluted. Conclusions Based on these results, future survey of rare, cryptic species in highly turbid lake systems should in the first instance include a broad scale eDNA survey, with sampling concentrated at outlet channels. Implications The likely most cost-effective approach to determining the presence/absence of rare species in lake systems is the collection of eDNA samples at outlet channels.

River regulation has reduced natural flow peaks in rivers globally, and in some cases has also reduced the occurrence of low-flows that expose the riverbed. Minimum low-flows are commonly mandated for temperate managed waterways in summer to maintain water quality and aquatic habitat for flora and fauna, at levels which prevent riverbed exposure. Very low flows that allow partial riverbed exposure may have many important roles in naturally impermanent waterways, including promoting plant recruitment. We conducted an in-situ field experiment in a regulated river by drawing down flows for two weeks in austral autumn to facilitate plant recruitment from the riverbed. We also conducted a concurrent ex-situ experiment in controlled conditions using sediment samples from field plots and subjecting them to exposure and inundation treatments. Two-week exposure of riverbed sediments was sufficient to trigger the germination of thousands of flood-tolerant riverine plants in both the in-situ and ex-situ experiments, but aquatic plants showed little response. Terrestrial plant seedlings were uncommon within the river-bed substrate. Seedlings were tolerant of early re-inundation but prolonged inundation resulted in senescence and mortality for non-aquatic plants. Very low flows in rivers for at least two weeks may facilitate recruitment of flood-tolerant riverine plants but the event timing and re-inundation regime will influence the likelihood of successful plant establishment. While there are potential risks for some aquatic taxa by implementing very low flows, this needs to be weighed against the potential benefits of riverbed exposure for promoting important biotic processes including plant recruitment.

ABSTRACT The (re)establishment of macrophytes is a key objective for wetland managers across the Murray–Darling Basin, Australia. Numerous factors could influence wetland macrophyte germination and growth in forested floodplain wetlands, including allelopathic substances, particularly from the litter of fringing trees, but the role of allelopathy in wetland plant germination and growth is not well understood. In the current study, the allelopathic effects of aqueous leachate from the litter of the river red gum ( Eucalyptus camaldulensis Dehn.) on the emergence and growth of wetland macrophytes (and other phototrophs) were studied in a mesocosm experiment. Sediments were collected from two wetlands in Gunbower Forest, Victoria. One wetland (Reedy Lagoon) supports a diverse range and high abundance of wetland plants, while an adjacent wetland (Barapa Swamp) is humo‐eutrophic and has low diversity and abundance of wetland macrophytes. Replicate sediment samples from both wetlands were exposed to four concentrations of leachate from E. camaldulensis leaf litter: High (75 mg/L as C), Medium (37.5 mg/L as C), Low (18.75 mg/L as C) and a Control (containing no leachate). After 90 days of incubation germinants were identified and counted to the lowest taxonomic level practicable, percent cover of filamentous algae was estimated, and the concentrations of chlorophyll a and phaeophytin were measured. There were statistically significantly more germinants in the Control treatment than in the three leachate treatments from the Reedy Lagoon sediment, and a statistically significant greater number of germinants in the Control than in the High treatments for Barapa Swamp sediment. At higher concentrations, the development of germinants was inhibited, with the vast majority unable to be identified beyond monocotyledon or dicotyledon due to lack of growth and with no dicotyledons present in the High treatment from either wetland. There was no noticeable effect of leachate concentration on the emergence of free‐floating species or on filamentous algae. The impact on phytoplankton growth was more complex, with a higher algal biomass in the Low treatments compared to the Control but a decrease at higher concentrations.

The captive breeding and release of threatened small-bodied freshwater fish is a common conservation method, yet many of these fish lack the behavioural profile to survive in the wild. Soft-release sites that provide wild-like experiences with minimal threat to survival can improve post-release outcomes. Here, we investigated whether captive-bred first generation Southern pygmy perch (Nannoperca australis) exposed to six months of soft-release experience develop natural behaviour. In laboratory tests, we compared the behaviour of fish from a hatchery, a soft-release site, or the wild in emergence, exploration, habitat choice, predator response, and novel food tests. As predicted, we found that fish from the soft-release site showed similar behavioural responses to wild-caught fish. However, soft-release fish were significantly larger (14.6 mm, 1.6 g advantage) and made greater use of refuge structures (basket ledges). Also, while trends suggested altered anti-predator responses, statistical support was limited, warranting further investigation. We conclude that soft-release experience enhances growth and shelter-seeking behaviour in this species, though further tests in a more natural environment should be undertaken to confirm ecologically important experience-dependent changes in behaviour. We recommend prioritising soft-release programmes that maximise natural foraging opportunities, reduce competition, and provide complex structures to support shelter use. Finally, the overall similarity in behaviour of fish from different environments suggests that, in this species, behaviour appears mostly inherited.

Amidst escalating climate change challenges, effective land use planning and decision-making are crucial for nurturing resilient and sustainable landscapes. Decision-makers often struggle with unintended consequences due to the intricate system dynamics, compounded by fragmented information and divergent stakeholder perspectives. This research integrates science, stakeholder engagement, and systems thinking to navigate the complexities of land use planning in response to climate change. We develop a decision-making framework for climate-cognisant sustainable land use planning, incorporating systems thinking principles. The framework uses validated expert system models to assess climate change impacts on agricultural land use. Through collaborative engagement with end users, it is refined to address specific regional challenges and opportunities. Applied within a case study in Victoria, Australia, and generalized for broader contexts, the framework provides a practical, systemic-intervention-driven process for better regional planning decisions amid evolving climate complexities. Keywords: Climate Change, Land Use Planning, Systems Thinking, Decision Making, Stakeholder Engagement

Background &amp; Aims<br/>Barapa Barapa Traditional Custodians have expressed interest in determining the presence and distribution of freshwater mussels in Gunbower Forest, as part of broader cultural objectives of healthy wetlands in this area.<br/>This project was a collaboration among Barapa Barapa Traditional Custodians, The Barapa Barapa Wamba Wemba Water for Country Steering Committee, North Central CMA and Charles Sturt University. The aim of the project was to determine the current status of freshwater mussels in wetlands of the lower part of the Gunbower Forest, to inform mussel population management, especially through water delivery.<br/>Besides being important culturally, intact freshwater mussel populations play important functional food web and water quality roles in rivers and wetlands, through their capacity to filter large amounts of water. In turn, mussels require healthy fish populations to complete their life cycle, because fish are hosts for their parasitic larvae, called glochidia.<br/>Methods<br/>In April-May 2023, freshwater mussel surveys were conducted by Barapa Barapa Traditional Custodians and North Central CMA staff in six wetlands of the lower Gunbower Forest: Reedy Lagoon, Barapa (Black) Swamp, Little Reedy Lagoon, Little Gunbower Creek, Green Swamp, and Corduroy Swamp.<br/>Mussels were surveyed using a combination of perimeter searches, looking for shells along the<br/>dry edge of the wetland, and more intensive timed searches, to look for live mussels in the water.<br/>The presence of shells during perimeter searches gave an indication of the likelihood of live mussels being present in a wetland, as well as an indication of past abundances. The timed searches provided data on the presence, relative abundance, spatial distribution, size structure and recruitment of live mussels.<br/>A total of 10.9 km of wetland perimeter was searched for shells (6 km of shallow-water zone perimeter, and 4.9 km of deep-water zone perimeter). The total search time for live mussels in the 6 wetlands was 18 person-hours. The surveys covered 87 ha (7%) of the total area of Gunbower Forest considered either permanent or semi-permanent wetland habitat.<br/>Results<br/>Of the 6 wetlands surveyed, live mussels and mussel shells were only found in Green and Corduroy swamps. A total of 15 shells (including shell fragments) and 12 live mussels were found. In 2-people hours of search time (2 sites, 1 hour search time each), 7 live mussels were found in Green Swamp, and in 3-people hours of search time (3 sites, 1 hour search time each), 5 live mussels were found in Corduroy Swamp. The distribution of mussels was seemingly haphazard, with no dense shoals found. Live mussels were found in depths ranging from 30-120 cm.<br/>All mussels and intact shells were identified as billabong mussels, Velesunio ambiguus. All of the mussels were above 55 mm, the size for sexual maturity.<br/>For wetlands where no live mussels were found (Barapa [Black] Swamp, Reedy Lagoon, Little Reedy Lagoon and Little Gunbower Creek), we cannot be certain that mussels are absent, but the lack of shells observed, either old or new, is a strong indication that mussels are most likely not present.

Abstract Freshwater fish are facing an extinction crisis on a global scale, with increasing demand for human water consumption driving the regulation and degradation of freshwater ecosystems. Flow regulation especially poses a threat to small‐bodied floodplain and creek specialist species through increasing population fragmentation and isolation, loss and degradation of habitats, and interactions with predators and competitors, resulting in reductions in species' range and abundance. Conserving and recovering many small‐bodied fish species will likely require translocation from wild habitats to refuge habitats to reduce extinction risk and provide buffers against catastrophic natural events (e.g., drought, bushfires). We assessed the value of semi‐artificial farm dams, an abundant feature in the Australian landscape, as interim refugia for the threatened southern pygmy perch Nannoperca australis (Percicthyidae). We compared the relative abundance, population size–structure and body condition of fish introduced (3–4 years prior) into three farm dams with those of three nearby creeks to assess the feasibility of farm dams as a resource to assist small‐bodied native fish conservation and recovery. Farm dams had higher abundance of fish, and equivalent size structure and body condition compared with creek populations, highlighting that suitable farm dams are a valuable and underutilized asset for threatened species' conservation globally.

ABSTRACT Groundwater recharge underpins water security in the highly allocated, semi-arid Campaspe River Basin, but its climate-sensitive future response remains poorly quantified, creating uncertainty for groundwater planning. This study assesses the impact of climate change on groundwater recharge in the Lower Campaspe River Basin using SWAT model calibrated with observed streamflow data for recharge projections. Future projections from two CMIP6 climate models (GFDL and CESM) under low (SSP126) and high (SSP585) emission scenarios were bias corrected using Quantile Mapping and used as inputs into the calibrated SWAT model. Results reveal strong inter-model variability, pronounced spatial contrasts with a north–south gradient, and significant differences across emission scenarios and future periods. Under SSP126, ensemble-average recharge is projected to increase by 62% in the near future, decline by 17% in the mid future, and rise again by 43% in the far future. In contrast, SSP585 simulations indicate consistent reductions in recharge, with average declines of 38, 26, and 32%, respectively. The findings highlight precipitation as the main driver of recharge, with CESM projecting stable or increased recharge under wetter conditions, while GFDL projects substantial declines under drier, warmer scenarios. These recharge projections provide a robust basis for sustainable groundwater planning in the region.