SEMINAR: MBF STUDENT SEMINAR ***TODAY FRI 11/9 @ 1PM*** DOMINIQUE LAZARRE & ESTHER GOLDSTEIN

[Pam Harris <pharris@rsmas.miami.edu>]

Pamela Harris

Marine Biology and Fisheries

Rosenstiel School of Marine & Atmospheric Science

University of Miami

4600 Rickenbacker Causeway/SLAB-118

Miami, FL 33149

(305) 421-4176

fax - (305) 421-4600

pharris@rsmas.miami.edu  

 

http://www.rsmas.miami.edu/academics/divisions/marine-biology-fisheries/

 

On 11/8/2012 10:56 AM, Pam Harris wrote:

 

MBF Student Seminar Series

 

Dominique Lazarre

Advisor: Dr. David Die

 

“Determining recruitment patterns by aging juvenile lionfish”

Some aspects of invasive lionfish reproductive biology remain uncertain. A histological examination of lionfish collected in North Carolina and the Bahamas showed gravid females were present throughout the year. Presence of gravid females however does not equate to spawning and successful recruitment of juveniles. This study aims to verify whether spawning results in successful recruitment by aging juvenile lionfish and creating an index of hatch dates. Otoliths were extracted, sectioned and polished from 72 juvenile lionfish collected in the Bahamas between July of 2007 and 2008. The number of daily increments was successfully enumerated for 62 of the otoliths, with each otolith counted three times. Otoliths were examined to determine the most appropriate reading axis. Readings were conducted by counting the increments from the otolith core to edge on the ventral (broader) side of each otolith. Increment counts were determined to increase in precision with each additional read. The number of days alive was assigned to each otolith by calculating a weighted age. Mean weighted age of samples was 109 days (std±24 days). Hatch dates were calculated by subtracting the weighted age from the collection date. Calculated hatch dates spanned each month of the year, suggesting that lionfish are successfully spawning throughout the year.

 

 

Esther Goldstein

Advisor: Dr. Su Sponaugle

“Comparative demography of a coral reef fish across vertical spatial scales”

With the contemporary global loss of coral reefs, deep reefs that are buffered from storms and temperature fluctuations may function as refugia that have the capacity to seed degraded shallow reefs through larval dispersal. The majority of reef fishes exhibit a complex life cycle with a pelagic larval stage and reef associated juvenile and adult stages. Consequently, fish are exposed to dynamic environments that can influence population demography and connectivity throughout the pelagic and post-settlement life stages. This study couples field collections with laboratory analyses to identify patterns in bicolor damselfish (Stegastes partitus) demography across multiple life stages on shallow (<10 m), deep (>20 m), and mesophotic (>30 m) reefs. Vertical spatial variability in fish demography will be assessed using otolith-derived traits for juvenile and adult fish and measures of adult reproductive investment. To identify processes that influence spatially explicit demographic trends, physical data, habitat surveys, and fish behavior will be measured in conjunction with gut content analyses and stable isotope studies to assess differences in fish diets and energy allocation across depths. Understanding spatial patterns in fish demography and the refugia function of deep reefs will help predict coral reef resilience and provide valuable information for marine spatial planning.

 

 

FRIDAY, NOVEMBER 9, 2012

1:00pm

RSMAS campus, S/A 103

Pamela Harris

Marine Biology and Fisheries

Rosenstiel School of Marine & Atmospheric Science

University of Miami

4600 Rickenbacker Causeway/SLAB-118

Miami, FL 33149

(305) 421-4176

fax - (305) 421-4600

pharris@rsmas.miami.edu  

 

http://www.rsmas.miami.edu/academics/divisions/marine-biology-fisheries/