The risks and rewards of using artificial habitat structures for wildlife conservation

Authors: Darcy J. Watchorn (Deakin University), Tenaya A. Duncan (Murdoch University), Mitchell A. Cowan (Charles Sturt University and the University of Western Australia).

Artificial habitats are a dichotomy in wildlife conservation, offering risks and rewards.

Many of the world’s natural environments are irreparably modified and damaged, and consequently, many species have lost critical habitat components they need to survive (Fischer and Lindenmayer, 2007). Increasingly, conservationists and developers seek to supplement these destroyed habitat components with artificial habitat structures—i.e., purposefully designed human-made substitutes for critical features of natural habitats that animals use to bask (Moore, 2019), reproduce (Knaepkens et al., 2004), hibernate (Latham and Knowles, 2008), and take refuge from predators (Bourke et al., 2017) and environmental stressors (Griffiths et al., 2018). They’re now used globally in marine, freshwater, and terrestrial environments for a diversity of taxa, including invertebrates (e.g., Green, 2005), reptiles (e.g., Souter et al., 2004), terrestrial and aquatic mammals (e.g., Harley, 2006; Kunnasranta et al., 2022), birds (e.g., Hart et al., 2016), amphibians (e.g., Latham and Knowles, 2008), and fish (e.g., Simpson et al., 2020). 

However, artificial habitat structures are a dichotomy for wildlife conservation. On one hand, when they are backed by sound science, they can enable positive conservation outcomes by facilitating the persistence and recovery of animal populations affected by habitat destruction and other threats at small spatial scales (Berthier et al., 2012). They can also provide unique opportunities for technologists and conservationists to collaborate (Callan et al., 2023, Parker et al., 2022). 

On the other hand, artificial habitat structures can facilitate negative ecological effects when implemented without appropriate research validating their benefit to the target population (Roy et al., 2009). For instance, many structures are implemented without proper controls, impeding our ability to determine their impact (Cowan et al., 2021). Understanding their effect is necessary because many don’t provide critical resources—such as food, shelter, or microclimate—for the target population, which can lead to an increased risk of predation (Skwarska et al., 2009, Cowan et al., 2020), exposure to fatal environmental conditions (Griffiths et al., 2018), disease and invasive species spread (Macreadie et al., 2011), or even a decline in genetic diversity (Fauvelot et al., 2009). Additionally, artificial habitat structures may also be embraced as a greenwashing mechanism to make unsustainable practices appear to be more environmentally responsible (Firth et al., 2020, Cowan et al., 2021); often via their inclusion in a biodiversity offset project—which are oftentimes ineffective (Lindenmayer et al., 2017; Saunders et al., 2022). In this way, their use may facilitate a further impingement on natural areas and habitat destruction (Firth et al., 2020). 

To ensure that artificial habitat structures lead to positive environmental outcomes for target populations, practitioners must be aware of these risks and how to reduce their likelihood of occurrence. It is paramount that their incorporation into conservation programs be underpinned by rigorous science (Watchorn et al., 2022). To this end, practitioners should ensure (1) the design is ecologically sound—i.e., appropriate design, construction, (Griffiths et al., 2018, Arida and Bull, 2008, Ebrahimi et al., 2012) and positioning in the landscape (De La Cruz et al., 2018); (2) they support the conservation of wildlife populations into the long term—i.e., once implemented, the response of fauna (e.g., survival, fecundity, population size, etc.,) to the structures should be monitored across relevant ecological spatial and temporal scales, and their effects compared with appropriate controls; (3) they do not serve as greenwashing mechanisms or inappropriate biodiversity offsets. 

Finally, and perhaps most importantly, we must not lose sight of the underlying threats causing species decline in the first instance. Artificial habitats generally don’t address these underlying threats, and once destroyed, natural habitats take a long time to recover (Haslem et al., 2012)—if they can recover at all.