東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Larval Fish Mortality and Vertical C...

Turley, Brendan D.

Linked to FindBook

Google Book

Amazon

博客來

Larval Fish Mortality and Vertical Chlorophyll Structures: Reexamination of the Stable Ocean Hypothesis in the Southern California Current.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Larval Fish Mortality and Vertical Chlorophyll Structures: Reexamination of the Stable Ocean Hypothesis in the Southern California Current./
Author:	Turley, Brendan D.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2019,
Description:	159 p.
Notes:	Source: Dissertations Abstracts International, Volume: 81-09, Section: B.
Contained By:	Dissertations Abstracts International81-09B.
Subject:	Biological oceanography. -
Online resource:	https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=22618190
ISBN:	9781392809594

Larval Fish Mortality and Vertical Chlorophyll Structures: Reexamination of the Stable Ocean Hypothesis in the Southern California Current.
Turley, Brendan D.

Larval Fish Mortality and Vertical Chlorophyll Structures: Reexamination of the Stable Ocean Hypothesis in the Southern California Current. - Ann Arbor : ProQuest Dissertations & Theses, 2019 - 159 p.

Source: Dissertations Abstracts International, Volume: 81-09, Section: B.

Thesis (Ph.D.)--University of South Carolina, 2019.

This item must not be sold to any third party vendors.

The natural mortality of fishes is an important component for understanding population dynamics. The larval stages of pelagic fishes living in the open ocean are particularly vulnerable to high rates of mortality, and fluctuations in these rates are thought to exert a large influence on the number of fish maturing into the spawning population. Early stage larval fishes are thought to undergo a critical period after hatching when they must find food or succumb to starvation. While the availability of suitable food for larval fishes is, on average, too low in the open ocean to support survival, patchy distributions of planktonic food can be vital habitat. The stable ocean hypothesis describes how wind mixing can influence this habitat through dilution of plankton patches and increase the mortality of larval fishes. In this dissertation, I reexamined the stable ocean hypothesis from three perspectives to understand how it might influence several key components of the California Current Ecosystem. First, I calculated larval mortality rates for five fishes (northern anchovy, Pacific sardine, Pacific hake, Pacific mackerel, and jack mackerel) from 1979 to 2015. Then I compared the mortality rates to indices of storm events and calm periods as a proxy for water column mixing and planktonic patchiness. Contrary to expectations, storm events did not negatively influence the survival of any of these species. In fact, mortality for Pacific hake decreased with an increased number of storms. Next, I examined the effect that storm events had on the vertical distribution of chlorophyll layers. I found that storms tended to decrease the occurrence of high-concentration chlorophyll layers in the water column. Finally, changes to the planktonic community composition within the chlorophyll layer was assessed. Significant variability associated with years and regions was found among sampled community compositions. Furthermore, a proxy for larval fish food exhibited considerable variability; however, the variability was not explained by the region, season, or year. Moreover, there were two peaks in biomass much higher the median value of the food proxy biomass and these events were dominated by potentially noxious algal species that may have negative implications for larval fish survival.Overall, evidence was found to support the notion that winds may influence the plankton communities larval fish rely upon, but, little support was found for a direct link to larval mortality. The stable ocean hypothesis may be important for fish recruitment in the California Current Ecosystem, but its influence appeared to be minimal on seasonal, regional, and interannual scales.

ISBN: 9781392809594Subjects--Topical Terms:

2122748
Biological oceanography.
Subjects--Index Terms:

Community ecology

Larval Fish Mortality and Vertical Chlorophyll Structures: Reexamination of the Stable Ocean Hypothesis in the Southern California Current.
LDR:03901nmm a2200361 4500 001 2280185
005 20210830065507.5
008 220723s2019 ||||||||||||||||| ||eng d
020 $a 9781392809594
035 $a (MiAaPQ)AAI22618190
035 $a AAI22618190
040 $a MiAaPQ $c MiAaPQ
100 1 $a Turley, Brendan D. $3 3558690
245 1 0 $a Larval Fish Mortality and Vertical Chlorophyll Structures: Reexamination of the Stable Ocean Hypothesis in the Southern California Current.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2019
300 $a 159 p.
500 $a Source: Dissertations Abstracts International, Volume: 81-09, Section: B.
500 $a Advisor: Rykaczewski, Ryan R.
502 $a Thesis (Ph.D.)--University of South Carolina, 2019.
506 $a This item must not be sold to any third party vendors.
520 $a The natural mortality of fishes is an important component for understanding population dynamics. The larval stages of pelagic fishes living in the open ocean are particularly vulnerable to high rates of mortality, and fluctuations in these rates are thought to exert a large influence on the number of fish maturing into the spawning population. Early stage larval fishes are thought to undergo a critical period after hatching when they must find food or succumb to starvation. While the availability of suitable food for larval fishes is, on average, too low in the open ocean to support survival, patchy distributions of planktonic food can be vital habitat. The stable ocean hypothesis describes how wind mixing can influence this habitat through dilution of plankton patches and increase the mortality of larval fishes. In this dissertation, I reexamined the stable ocean hypothesis from three perspectives to understand how it might influence several key components of the California Current Ecosystem. First, I calculated larval mortality rates for five fishes (northern anchovy, Pacific sardine, Pacific hake, Pacific mackerel, and jack mackerel) from 1979 to 2015. Then I compared the mortality rates to indices of storm events and calm periods as a proxy for water column mixing and planktonic patchiness. Contrary to expectations, storm events did not negatively influence the survival of any of these species. In fact, mortality for Pacific hake decreased with an increased number of storms. Next, I examined the effect that storm events had on the vertical distribution of chlorophyll layers. I found that storms tended to decrease the occurrence of high-concentration chlorophyll layers in the water column. Finally, changes to the planktonic community composition within the chlorophyll layer was assessed. Significant variability associated with years and regions was found among sampled community compositions. Furthermore, a proxy for larval fish food exhibited considerable variability; however, the variability was not explained by the region, season, or year. Moreover, there were two peaks in biomass much higher the median value of the food proxy biomass and these events were dominated by potentially noxious algal species that may have negative implications for larval fish survival.Overall, evidence was found to support the notion that winds may influence the plankton communities larval fish rely upon, but, little support was found for a direct link to larval mortality. The stable ocean hypothesis may be important for fish recruitment in the California Current Ecosystem, but its influence appeared to be minimal on seasonal, regional, and interannual scales.
590 $a School code: 0202.
650 4 $a Biological oceanography. $3 2122748
653 $a Community ecology
653 $a Harmful algal bloom
653 $a Larval ecology
653 $a Oceanography
653 $a Pelagic
653 $a Turbulence
690 $a 0416
710 2 $a University of South Carolina. $b Marine Science. $3 1019496
773 0 $t Dissertations Abstracts International $g 81-09B.
790 $a 0202
791 $a Ph.D.
792 $a 2019
793 $a English
856 4 0 $u https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=22618190