Table 1. Sources of mother-calf pairs data.

Site: site where the survey was done (from north to south): Piedras blancas (PB), Ojo de Liebre Lagoon (OLL), San Ignacio Lagoon (SIL), Santo Domingo Channel (SDCh) north of Bahia Magdalena; year: years when the surveys were done; period: months of the year when the surveys were done; led by: person who led the surveys, VRB: El Vizcaino Biosphere Reserve; Source: reference where the data was taken.

Site	Years	Period	Led by	Sources
PB	1997–2000	Mar-Jun	Perryman W	[27]
	2000–2009	Mar-Jun	Perryman W	[30]
OLL	1980–1983	Feb	Fleischer L	[5]
	1985–2000	Feb	Sánchez J	[5]
	2001–2002	Feb	Urbán J	[5]
	2003–2009	Feb	Personnel VBR	This paper
SIL	1997–2002	Feb	Swartz S, Urbán J	[5]
SDCh	1997–2000	Feb	Péréz-Cortés H	[5]
	2001–2002	Feb	Urbán J	[5]