Research Technical Report

California Coastal Kelp Resources, Monterey Bay National Marine Sanctuary, Summer 2000

Van Wagenen, R.F. (Feb 2001)

Final Report, 90pp.

PRINCIPLE FINDINGS

The principle findings from the 2000 Monterey Bay National Marine Sanctuary kelp resource inventory were summarized, by CDF&G kelp bed numbers, as follows:

1. 2000 kelp resource extent,
2. 1999 kelp resource extent, and
3. Comparisons of the 1999 and 2000 sanctuary-wide coastal kelp resource.

1. Summary of the 2000 Sanctuary-wide Kelp Resource Extent

The total 2000 surface kelp canopy resource, within the MBNMS (CDF&G kelp beds 208-225), occupied canopy/planimeter areas of 17.051 sq. mi. and 24.663 sq. mi., respectively. The relative density index was measured at .71.

2. Summary of the 1999 Sanctuary-wide Kelp Resource Extent

The total 1999 surface kelp canopy resource, within the MBNMS (CDF&G kelp beds 208-225), occupied canopy/planimeter areas of 14.053 sq. mi. and 22.358 sq. mi., respectively. The relative density index was measured at .63.

3. Summary Comparisons of the 1989-99 Sanctuary-wide Kelp Resource

The total sanctuary-wide kelp resource canopv area siqnificantly increased (p=,05) from 14.053 sq. mi. to 17.451 sq. mi., which represented a 24% increase of surface canopy from that measured in 1999. The 1999-2000 total kelp bed planimeter area also significantly increased from 22.358 to 24.663 sq. mi., which represented a 10% increase of planimeter extent. The reiative density index also significantly increased from .63 (1999) to .71 (2000).

Although virtually all canopies within the survey range showed in increase in surface extent, the greatest increase was observed within the Monterey Bay itself (CDF&G canopies 222, 221 and 220). Increases in canopy areas of 120%, 206%, and 66%, respectively, were noted. In addition, increases in planimeter areas of 59%, 33%, and 43%, respectivtely, were also observed within these canopies.

The only canopy to experience a substantial loss in surface extent was canopy 208 (Cambria to Pt. Estero), which was reduced by 24% in canopy area and 14% in planimeter area.