Table 2.
pH tolerance of fertilization and early development, and pH levels producing impaired fertilization and development, in studies of sea urchins, where pH was lowered by the treatment of sea water with CO2 gas, with control fertilization ≥80–90% and development ≥75%. n.d., no data. (Asterisk indicates the individual cleavage stages scored.)
| species | pH range fertilization | pH fertilization <60–70% | pH range normal early development | pH normal development <60–70% | reference |
|---|---|---|---|---|---|
| Strongylocentrotus purpuratus | 7.3–8.2 | 7.0 | 7.5–8.3 | 7.3 | Bay et al. (1993) |
| Hemicentrotus pulcherrimus | 7.4–8.0 | 7.0 | 7.6–8.0* | 7.4 | Kurihara & Shirayama (2004) |
| Arbacia punctulata | 6.9–8.6 | 6.8 | 7.4–8.6 | 6.8 | Carr et al. (2006) |
| Echinometra mathaei | 7.6–8.1 | 7.4 | n.d. | n.d. | Kurihara & Shirayama (2004) |
| Heliocidaris erythrogramma | 7.6–8.3 | n.d. | 7.8–8.3 | n.d. | this study |
| Heliocidaris tuberculata | 7.6–8.3 | n.d. | n.d. | n.d. | M. Byrne, P. Selvakumaraswamy & N. A. Soars (2008, unpublished data) |