City governments increasingly use environmental sensing technologies and resulting data to respond to urgent planetary challenges such as climate change and biodiversity loss. Although these initiatives are positively focused towards conservation, as a number of researchers have noted, biodiversity conservation projects are largely embedded in positivist scientific discourse and often do not question the neoliberal capitalist framework cities are operating within (Brockington & Duffy, 2010; Büscher et al., 2012). The environmental sensing technologies used to track nonhuman species for conservation purposes are designed by humans to understand the environment and its inhabitants, therefore, they are geared towards human perception (Gabrys, 2016). Moreover, as Adams (2019) has argued, these approaches often exercise a form of spatial control over nonhuman life and their movements (Adams, 2019) that also reinforce human exceptionalism (Clarke et al., 2019). Similarly, the biodiversity databases confine nonhuman beings into matrices of knowledge that commodify them (Youatt, 2008) as sources of ‘natural capital’ (Costanza et al., 1998). Building on this discourse, we argue that techno-scientific approaches alone are not sufficient to address urban biodiversity loss. Our research also finds previous studies and current urban governance approaches have not successfully addressed the increasing biodiversity concerns. The failure to address biodiversity concerns has political and ethical implications for the future of urban life – both human and nonhuman. This paper argues for a different methodological approach to biodiversity conservation in city governance – speculating desirable future(s). The paper is divided into three sections. First, it identifies issues embedded in urban science and smart city data-driven approaches to biodiversity conservation. Second, under the rubric of more-than-human studies (Houston et al., 2018; Loh et al., 2020; Todd, 2015; Van Dooren et al., 2016) and critical data studies (Iliadis & Russo, 2016), it proposes a turn to desirable future(s) approach in urban data governance by engaging with methodologies such as value scenarios (Nathan et al., 2007), urban imaginaries (Estrada-Grajales et al., 2018), and speculative design fiction (Dunne & Raby, 2013). Third, it discusses the potential of these methodologies to address some identified issues in data-driven approaches to city governance for more genuine sustainability outcomes and better urban policies. In this paper’s concluding discussion, we articulate a practical set of guidelines; on how speculative methodologies can offer better urban policies relating to biodiversity conservation.