This species was elevated from its previous status as a subspecies of Bufo bufo by Recuero et al. (2012).

European regional assessment: Least Concern (LC)
EU 27 regional assessment: Least Concern (LC)

The Spiny Toad (Bufo spinosus) is assessed as Least Concern in view of its wide distribution and presumed large population. However, declines have been observed in some parts of its range and monitoring is required. Further research is required to confirm its distribution with respect to Bufo bufo.

This species occurs from the island of Jersey (Arntzen et al. 2014) in the north, through western and southern France, Andorra (Arntzen et al. 2013) and the Iberian Peninsula. The full extent of its range is possibly not fully known, and is still being investigated in central France (Arntzen et al. 2013, Trujillo et al. 2017), where it occurs in some areas with or near Bufo bufo, with which it can be confused. It is known to occur from about sea level to 2,600 m in the Spanish Pyrenees (García-París 2004). It occurs in the Spanish enclave of Ceuta in North Africa.

The range of the species extends out of the European region to North Africa (Morocco, northern Algeria and extreme north-western Tunisia; Ben Hassine and Nouira 2012, Beukema et al. 2013; Ben Hassine and Escoriza 2014, 2017), where its range is fragmented (Arntzen et al. 2013).

This species is generally common over much of its range, though some declines have been observed, e.g. in Jersey (Wilkinson et al. 2007) and Spain. Due to ongoing local declines in the extent and quality of its habitat, the population is inferred to be decreasing.

This is a widespread species in western Europe with a large latitudinal range. It exploits a variety of habitats across that range including woodlands, shrublands, heathlands, dunes and more arid areas, as well as anthropogenically modified habitats such as farmland and gardens. In the north of its range (Jersey), it breeds commonly in small, still ponds of anthropogenic origin, as well as temporary (e.g. dune slack) ponds (Wilkinson et al. 2007), but exhibits broader habitat preferences further south, also breeding in more permanent water bodies including streams and stream pools (Iberia) (Da Fonseca et al. 2008, Gómez-Rodríguez et al. 2009, Ben Hassine and Escoriza 2014). In southern France, it is known from a broad range of natural and artificial breeding sites, although it does not tolerate salinity and is absent from coastal habitats (Geniez and Cheylan 2012; P.A. Crochet pers. comm. 2020). It readily colonizes modified and fully artificial habitats (such as concrete cisterns) and is more tolerant than sympatric frogs of the presence of fish (Crochet et al. 2004, Geniez and Cheylan 2012; P.A. Crochet pers. comm. 2020).

The species begins reproduction much earlier in the year, on average, than other, similar species (including B. bufo) with spawning occurring commonly from just after the annual thermal minimum (in December and January) through to March or even later, in both the north and south of its range (e.g. Díaz-Paniagua et al. 2005, Cistude Nature 2010, Artnzen et al. 2014). Reproduction is very variable, however, and may be delayed by a lack of suitable water bodies.

The maximum size of males of this species is 16 cm (11 in the north of the range), with females being larger than males (Speybroeck et al. 2016). Hemelaar (1988) reported the life history of a subpopulation from France and found that males generally reach sexual maturity at four to five years of age and females at five to six, although a small proportion can be sexually mature at three (male) or four (female) years. J. Wilkinson (pers. comm. August 2018) suggests that males can reach maturity as young as two years of age; P.A. Crochet (pers. comm. 2020) considers that very few if any males are likely to mature this young. Longevity is 12 years for males and 15 for females (J. Wilkinson pers. comm. 2018).

There are generally no major threats to this common species. However, some subpopulations may be affected by deforestation, drainage of wetlands, pollution, agricultural intensification, urbanisation, desertification, mortality on roads during migration (of which this species is a "frequent victim"; J. Ben Hassine pers. comm. 2020), increased UV-B radiation and persecution. Land-use changes (including agricultural practices and urbanisation) and climate change are also likely to impact some subpopulations by reducing foraging areas and breeding site availability, as well as causing fragmentation (J. Wilkinson pers. comm. August 2018). It is however, not clear whether these species have negative impacts on B. spinosus where they co-occur (Chillasse et al. 2002; Ben Hassine and Escoriza 2014, 2017; Escoriza 2018).

The species has declined extensively in Spain due to habitat loss and aridity (I. Martínez-Solano pers. comm. August 2019). In Spain, it was persecuted as it was seen as 'ugly', however, as local awareness is increasing that the species is being seen in lower numbers, persecution is decreasing (I. Martinez-Solano pers. comm. September 2019). In Spain, they are also affected by road mortality, as well as by predation of eggs and tadpoles by invasive crayfish (Procambarus clarkii). Since they are not good climbers or swimmers, they often die trapped in man-made waterbodies such as water tanks and cisterns, abandoned or in use.

Chytridiomycosis is a potential threat to the species and has been reported in some Spanish subpopulations. Species distribution modelling projects a decrease of  over 50% of the species' potential range in the period 2041-2070 (Araújo et al. 2011).

There are no records of this species being utilised.

Conservation Actions In-Place
The species is present in numerous protected areas and is protected under the Conservation of Wildlife Law in Jersey. It is listed in Appendix III of the Bern Convention and is protected by national and sub-national legislation in some countries. It is considered to be Near Threatened nationally in Spain, because of recent declines due to habitat loss, as well as progressive aridity. It is, however, one of the three native amphibian species not protected by national law in Spain (I. Martínez-Solano pers. comm. September 2019). In parts of this species range, mitigation measures to reduce road kill have been established. In Spain, artificial breeding sites have been found to be valuable (Caballero-Díaz et al. 2020).

Research Needed
Further research needs to be conducted into the threats affecting this species (J. Wilkinson pers. comm. August 2018), and further assessment is likely necessary when peripheral subpopulations have been explicitly investigated in the knowledge that the species is distinct from B. bufo (J. Wilkinson pers. comm. August 2018). Population monitoring is required to assess population trends and verify the general feeling that the species is in sharp decline, especially in central and southern Spain.