. The ecological impact of beach nourishment with dredged materials on the intertidal zone at Bogue Banks, North Carolina . Figure 20. Seasonal variation in the density of E. tatipoida popu- lations at the nourishment beach at Fort Macon, June 1977 to August 1978, and the comparison beach at Emerald Isle, September 1977 to August 1978. The actual period of nourishment is represented by a slashed line below the X-axis. in May when repopulation was well underway at both beaches. This recuitment lag resulted from the failure of adult Emevita to recolonize at Fort Macon (Fig. 21). Only adult Emevi
. The ecological impact of beach nourishment with dredged materials on the intertidal zone at Bogue Banks, North Carolina . Figure 20. Seasonal variation in the density of E. tatipoida popu- lations at the nourishment beach at Fort Macon, June 1977 to August 1978, and the comparison beach at Emerald Isle, September 1977 to August 1978. The actual period of nourishment is represented by a slashed line below the X-axis. in May when repopulation was well underway at both beaches. This recuitment lag resulted from the failure of adult Emevita to recolonize at Fort Macon (Fig. 21). Only adult Emevita were present on the Emerald Isle beach when repopulation began in April. These individuals had overwintered offshore and were returning to the beach where they would breed. As spring progressed, a greater proportion of the population was contributed by new recruits in the lower size classes. These smaller individuals represented recruitment cohorts from pelagic larval stocks or the young of the year. The first individuals to arrive on the Fort Macon beach were not the overwintering adults but the young of the year juveniles from pelagic larval stocks. While comparative density data for June (Fig. 20) indicated that mole crab densities were similar for both beaches, the size class composition was drastically different (Fig. 21) Where the Emerald Isle demographic table (Fig. 21) displays a complex assort- ment of size classes representing at least two year classes, the Fort Macon table (Fig. 21) shows only several cohorts of young of the year crabs. 39
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Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjectecology
