Planktonic larvae of many marine organisms are increasingly being exposed and required to respond to a changing physical environment. As Strongylocentrotus purpuratus adults occupy intertidal and subtidal waters, many questions remain about how populations residing at different depths adequately prepare their offspring to cope with different levels of UVR. In this study, S. purpuratus adults were collected from two intertidal and two subtidal (15 m) sites from the central coast of CA to compare UV tolerance in offspring. UVA (321–400 nm) and UVB (280–320 nm) measurements at the four collection sites were at minimal or absent levels in subtidal sites. Our study found that offspring from intertidal populations have a less severe developmental delay when exposed to environmentally relevant levels of UVR using artificial lighting than offspring from subtidal populations. The mean percent cleavage delay for UV-treated embryos relative to the controls was 17.6% for intertidal sites and 23.4% for subtidal sites. Although these embryos are members of the same species and share a common genetic background, they differ in their phenotype and chances of survival due to differences in maternal resources. This suggests that environmental UV cues or additional environmental cues experienced by intertidal mothers may reduce the negative effects of UV exposure during early development. To further explore the role of maternal investment, we are using a proteomic approach to assess differences in protein expression between eggs from intertidal and subtidal populations. This will offer insight into how protein variation provides embryos with a rapid response to stress during early development.