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Full-Text Articles in Biology
The Illusion Of Plenty: Hyperstability Masks Collapses In Two Recreational Fisheries That Target Fish Spawning Aggregations, Brad E. Erisman, Larry G. Allen, Jeremy T. Claisse, Daniel J. Pondella Ii, Eric F. Miller, Jason H. Murray
The Illusion Of Plenty: Hyperstability Masks Collapses In Two Recreational Fisheries That Target Fish Spawning Aggregations, Brad E. Erisman, Larry G. Allen, Jeremy T. Claisse, Daniel J. Pondella Ii, Eric F. Miller, Jason H. Murray
Daniel Pondella
Fisheries that target fish spawning aggregations can exhibit hyperstability, in which catch per unit effort (CPUE) remains elevated as stock abundance declines, but empirical support is limited. We compiled several fishery-dependent and fishery-independent data sets to assess stock trends in the barred sand bass (Paralabrax nebulifer) and the kelp bass (Paralabrax clathratus) in southern California, USA, evaluate the interaction between spawning aggregations and fishing activities, and test for hyperstability. Annual and seasonal trends from fisheries and population data indicate that regional stocks of both species have collapsed in response to overfishing of spawning aggregations and changes in environmental conditions. The …
Decadal-Scale Changes In Southern California Sciaenids Under Different Levels Of Harvesting Pressure, Eric F. Miller, Daniel J. Pondella Ii, D Shane Beck, Kevin T. Herbinson
Decadal-Scale Changes In Southern California Sciaenids Under Different Levels Of Harvesting Pressure, Eric F. Miller, Daniel J. Pondella Ii, D Shane Beck, Kevin T. Herbinson
Daniel Pondella
A unique 38-year time-series of power-plant entrapment data collected across ∼170 km of the southern California coastline was examined to describe the decadal-scale trends in common Southern California Bight sciaenid abundance in relation to oceanographic conditions. Adult catches for five of seven species declined at differing rates and severity. Declines of up to 94% were detected in historically common species such as Genyonemus lineatus, whereas historically less abundant species have increased dramatically, e.g. Umbrina roncador (2626%). Over time, the entrapped community became increasingly influenced by species with more southerly distributions, indicated by a significant decline in the average latitudinal midpoint …
The Decline And Recovery Of Four Predatory Fishes From The Southern California Bight, Daniel J. Pondella Ii, Larry G. Allen
The Decline And Recovery Of Four Predatory Fishes From The Southern California Bight, Daniel J. Pondella Ii, Larry G. Allen
Daniel Pondella
What to do about fisheries collapse and the decline of large fishes in marine ecosystems is a critical debate on a global scale. To address one aspect of this debate, a major fisheries management action, the removal of gill nets in 1994 from the nearshore arena in the Southern California Bight (34°26′30″N, 120°27′09″W to 33°32′03″N, 117°07′28″W) was analyzed. First, the impetus for the gill net ban was the crash of the commercial fishery for white seabass (Atractoscion nobilis; Sciaenidae) in the early 1980s. From 1982 to 1997 catch remained at a historically low level (47.8 ± 3.0 mt) when compared …
Phylogeography Of The Flag Cabrilla Epinephelus Labriformis (Serranidae): Implications For The Biogeography Of The Tropical Eastern Pacific And The Early Stages Of Speciation In A Marine Shore Fish, Mathew T. Craig, Phillip A. Hastings, Daniel J. Pondella Ii, D. Ross Robertson, Jorge A. Rosales-Casián
Phylogeography Of The Flag Cabrilla Epinephelus Labriformis (Serranidae): Implications For The Biogeography Of The Tropical Eastern Pacific And The Early Stages Of Speciation In A Marine Shore Fish, Mathew T. Craig, Phillip A. Hastings, Daniel J. Pondella Ii, D. Ross Robertson, Jorge A. Rosales-Casián
Daniel Pondella
To examine the role of previously described biogeographical boundaries in shaping phylogeographical relationships within and among two putative eastern Pacific sibling species, the flag cabrilla, Epinephelus labriformis and the Clipperton grouper, Epinephelus clippertonensis (Serranidae).
Evaluation Of Eelgrass Mitigation And Fishery Enhancement Structures In San Diego Bay, California, Daniel Pondella Ii
Evaluation Of Eelgrass Mitigation And Fishery Enhancement Structures In San Diego Bay, California, Daniel Pondella Ii
Daniel Pondella
To offset habitat loss and increase fishery production, an eelgrass mitigation habitat was completed in San Diego Bay, California in 1997. This mitigation effort consisted of the transplantation of eelgrass, Zostera marina L., in the western portion of the bay. In addition to the establishment of a new eelgrass bed, four enhancement reefs made of either quarry rock or concrete rubble were created to further enhance fishery stocks and the area's ecosystem. Two design criteria and a direct comparison between quarry rock and concrete reefs were examined in this 5-yr pilot program. The newly created eelgrass habitat quickly performed at …
Biogeography Of The Nearshore Rocky-Reef Fishes At The Southern And Baja California Islands, Daniel Pondella, Brooke Gintert, Jana Cobb, Larry Allen
Biogeography Of The Nearshore Rocky-Reef Fishes At The Southern And Baja California Islands, Daniel Pondella, Brooke Gintert, Jana Cobb, Larry Allen
Daniel Pondella
No abstract provided.
Speciation In The Central American Seaway: The Importance Of Taxon Sampling In The Identification Of Trans-Isthmian Geminate Pairs, Matthew T. Craig, Philip A. Hastings, Daniel J. Pondella Ii
Speciation In The Central American Seaway: The Importance Of Taxon Sampling In The Identification Of Trans-Isthmian Geminate Pairs, Matthew T. Craig, Philip A. Hastings, Daniel J. Pondella Ii
Daniel Pondella
Aim To create a molecular phylogenetic hypothesis for the closely related serranid genera Alphestes Bloch and Schneider and Dermatolepis Gill and assess the role of the Panamanian Isthmus in speciation within these reef fishes. Location Tropical eastern Pacific, Caribbean, and Indian Oceans. Methods Sequence data from one nuclear (TMO-4C4) and three mitochondrial genes (16S, 12S, and cytochrome b) were used in maximum parsimony and maximum likelihood analyses. Results Here we show that previously hypothesized trans-isthmian geminate species are not each other's closest living relatives. Species of Alphestes Bloch and Schneider in the eastern Pacific are sister taxa indicating post-closure speciation. …
Fish Production Of A Temperate Artificial Reef Based On The Density Of Embiotocids (Teleostei: Perciformes), Daniel J. Pondella Ii, John S. Stephens Jr., Matthew T. Craig
Fish Production Of A Temperate Artificial Reef Based On The Density Of Embiotocids (Teleostei: Perciformes), Daniel J. Pondella Ii, John S. Stephens Jr., Matthew T. Craig
Daniel Pondella
The abundance of two embiotocids (Embiotoca jacksoni and Rhacochilus vacca) was surveyed continually from 1974 to 1998 on the breakwaters comprising King Harbor in Redondo Beach, California, and a nearby natural rocky-reef as a reference. Embiotocids provide an interesting model for reef-fish production because they are viviparous and their entire ontogeny can be observed on the reefs. We deduce that the two reef populations of both species were stable at their carrying capacity. This carrying capacity was greater in King Harbor throughout the study. We also report a linear decline in survival of juveniles of both species over the 25-year …
Larval Productivity Of A Mature Artificial Reef: The Ichthyoplankton Of King Harbor, California, 1974–1997, John Stephens Jr, Daniel Pondella Ii
Larval Productivity Of A Mature Artificial Reef: The Ichthyoplankton Of King Harbor, California, 1974–1997, John Stephens Jr, Daniel Pondella Ii
Daniel Pondella
Do artificial reefs serve as productive marine fish habitats (sources) or do fish assemblages of such reefs contribute little to the gene pool of succeeding generations (sinks)? Using data from a 24-year study of the breakwater at King Harbor (California, USA), annual densities of reef fish larvae were compared with densities observed elsewhere in the Southern California Bight. Larval production at King Harbor has decreased over the study period, as has the size of the fish assemblage. Both declines may be related to recorded increases in water temperature. Larval densities from similar water depths (0–15 m) throughout the bight vary …
Demographic Parameters Of Golden Spotted Rock Bass Paralabrax Auroguttatus From The Northern Gulf Of California, Daniel Pondella Ii, Larry G. Allen, Jorge A. Rosales Casian, Tim E. Hovey
Demographic Parameters Of Golden Spotted Rock Bass Paralabrax Auroguttatus From The Northern Gulf Of California, Daniel Pondella Ii, Larry G. Allen, Jorge A. Rosales Casian, Tim E. Hovey
Daniel Pondella
The sex ratios, growth, and mortality of the golden spotted rock bass Paralabrax auroguttatus (Serranidae) were determined for populations from Islas Encantadas and Bahía de los Angeles in the Gulf of California. Specimens ranged from 137 to 479 mm standard length and from 135 to 3,100 g. Sagittal otoliths were used to determine age. A von Bertalanffy model of growth for both populations combined was estimated as Lt = 474.4·(1 − e −0.115( t + 2.093)), where Lt is fish length at age t. This model is comparable to those for other rock basses. The relationship between length and weight …
A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Daniel J. Pondella Ii, James M. Allen, Mark Helvey
A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Daniel J. Pondella Ii, James M. Allen, Mark Helvey
Daniel Pondella
Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …