Publication Date:
2022-05-25
Description:
Submitted in partial fulfillment of the requirements for the degree of
Doctor of Philosophy
at the
Massachusetts Institute of Technology
and the
Woods Hole Oceanographic Institution
September 2005
Description:
The geographic distribution and dynamics of coastal benthic populations are shaped by physical biological
interactions affecting larval dispersal and the demography of juvenile and adult
individuals. This thesis focused on nearshore patterns of larval distribution and regional patterns
in demography of intertidal barnacles in Southern and Baja California. Horizontal and vertical
distributions, and the mortality rates of larvae, were assessed from short tenn (i.e. days) smallscale
observations (0.1-1 km) in nearshore waters. Observations on spatial variability of adult
barnacle demography were gathered over 1.5 years at scales of hundreds of kilometers.
Stage-specific horizontal distributions and nearshore current measurements suggested that larvae
of Balanus glandula and Chthamalus spp. may experience limited dispersal. High mortality rates
could further limit travel distances and the exchange of individuals among disjunct populations.
Data on vertical distributions indicated that nauplii and cyprids of Balanus nubilus and Pollicipes
polymerus occur at different depths. Nauplii remained near the surface at all times, whereas
cyprids occurred in the bottom half of the water column. Such distributions, combined with
vertical variability in horizontal flows, might cause the observed horizontal segregation ofnauplii
and cyprids.
Differences in survival, growth rate,· size structure, and per capita fertility of adult Balanus
glandula were observed between Dana Point (Southern California) and Punta Baja (Baja
California), a site located near the species' southern limit of distribution. Effects of spatial
differences in demography on population persistence were assessed with a stage-structured matrix
model. Model analyses indicated that the Punta Baja population is more susceptible to
environmental stochasticity and more prone to local extinction than populations located further
north.
This thesis emphasizes the importance of characterizing factors that affect the dynamics of
benthic populations at mUltiple spatial-temporal scales, and the usefulness of small· scale highfrequency
observations of nearshore phenomena, especially in relation with the dispersal of
larvae.
Description:
I must thank the
Chilean MIDEPLAN (Ministerio de Plartificacion y Cooperacion), which provided funds
for the first three years of my doctoral studies through a Presidential Fellowship (Beca
Presidente de la Republica). Tuition, stipend, and research funds for the rest of my time.
as a Joint Program student carne from National Science Foundation grants OCE-0083976
and OCE-9986627 to my thesis supervisor (Jesus Pineda), and through the WHOI
Academic Programs Office.
Keywords:
Benthic animals
;
Larvae
;
Dispersal
Repository Name:
Woods Hole Open Access Server
Type:
Thesis
Format:
application/pdf
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