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The Effect Of 6-Methoxybenzoxazolinone On Reproductive Condition In The Hispid Cotton Rat, Sigmodon Hispidus, Vera Lee Adams Jul 1993

The Effect Of 6-Methoxybenzoxazolinone On Reproductive Condition In The Hispid Cotton Rat, Sigmodon Hispidus, Vera Lee Adams

Biological Sciences Theses & Dissertations

A non-estrogenic hormone, 6-methoxybenzoxazolinone (6-MBOA), found in young growing grasses, has been shown to be a reproductive initiator in several herbivorous rodents. However, the mechanism by which 6-MBOA initiates reproduction has not been determined. Many believe that 6-MBOA represents a reliable cue that the vegetative growing season has begun, but it is unknown whether this hormone is a primary cueing mechanism or if it works in conjunction with other environmental factors. Therefore, a controlled laboratory experiment was conducted using male and female Sigmodon hispidus, the hispid cotton rat, to determine whether different dosages of 6-MBOA (4μg, 40 …


Age And Growth Of Larval And Juvenile Atlantic Croaker, Micropogonias Undulatus, From The Middle Atlantic Bight And Estuarine Waters Of Virginia, Stephen W. Nixon Jul 1993

Age And Growth Of Larval And Juvenile Atlantic Croaker, Micropogonias Undulatus, From The Middle Atlantic Bight And Estuarine Waters Of Virginia, Stephen W. Nixon

Biological Sciences Theses & Dissertations

Sagittal otoliths were used to determine the age and growth of 605 larval and juvenile Atlantic croaker, Micropogonias undulatus, collected in the Middle Atlantic Bight (MAB) and estuarine waters of Virginia. A Laird-Gompertz model (r2 = 0.95) was used to describe the growth of croaker up to 65 mm standard length (SL) and 142 days (t): S1(t) = 2.657 Exp {4.656 [1-Exp (-0.008lt)]}; SL(t) = standard length at day t. Generally, croaker collected inshore were larger and older than those collected offshore, indicating estuarine immigration from offshore spawning grounds. Back-calculated hatch-dates indicated spawning over an 8- month period …


The Prairie Naturalist Volume 25. No. 2. June 1993 Jun 1993

The Prairie Naturalist Volume 25. No. 2. June 1993

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

CONTENTS

RAPID GROWTH OF CHANNEL CATFISH IN FLAMING GORGE RESERVOIR, WYOMING ▪ C. B. Alexander and W. A. Hubert

MANAGEMENT EVALUATION OF BODY CONDITION AND POPULATION SIZE STRUCTURE FOR PADDLEFISH: A UNIQUE CASE ▪ M L. Brown and B. R. Murphy

DISTRIBUTION OF THE RIBBON LEECH IN NORTH DAKOTA ▪ C. M. Pennuto and M. G. Butler

SELENIUM IN EARED GREBE EMBRYOS FROM STEWART LAKE NATIONAL WILDLIFE REFUGE, NORTH DAKOTA ▪ M. M. Olson and D. Welsh

USING GEOGRAPHIC VARIATION TO PREDICT BREEDING LOCALES OF …


Fisheries Research Report No.100 - The Impact Of Trawling For Saucer Scallops And Western King Prawns On The Benthic Communities In Coastal Waters Off South-Western Australia, L. J.B. Laurenson, P. Unsworth, J. W. Penn, R. C.J. Lenanton Jun 1993

Fisheries Research Report No.100 - The Impact Of Trawling For Saucer Scallops And Western King Prawns On The Benthic Communities In Coastal Waters Off South-Western Australia, L. J.B. Laurenson, P. Unsworth, J. W. Penn, R. C.J. Lenanton

Fisheries Research Reports

A two year study was undertaken to collect data for the assessment of the impact of the saucer scallop and western king prawn trawl fisheries on the benthic communities in coastal waters off south western Australia, between 31°20'5 and 34°23'5 latitude.

Monitoring of reported commercial landings, on-board sampling of commercial catches, research vessel trawl surveys, experimental and exploratory trawling, and underwater television observations, have enabled the development of an extensive data-base on the fishery and benthic communities of the region.

These data indicate that the existing fishery operates on a number of relatively small, discrete grounds where saucer scallops or …


Review Of Bag And Size Limit Proposals For Western Australian Recreational Fishers., F. B. Prokop May 1993

Review Of Bag And Size Limit Proposals For Western Australian Recreational Fishers., F. B. Prokop

Fisheries Management Papers

The Fisheries Department of WA and the Recreational Fishing Advisory Committee (RFAC), which is the peak body representing recreational fishers in WA, have been very pleased with the response to the implementation of two year review of recreational fisheries. Fisheries, RFAC and the fishing community recognise that the two year review was the first step in the continually evolving process of management of recreational fisheries. Since the new bag and size limit regulations were introduced in December 1991, there have been many suggestions for refinement and improvement. This management paper includes the most common and best suggestions for future management. …


Fisheries Management Paper No 53 - Rock Lobster Industry Advisory Committee - Report To The Minister For Fisheries And Management Arrangements For 1992/93, Fisheries Department Of Western Australia May 1993

Fisheries Management Paper No 53 - Rock Lobster Industry Advisory Committee - Report To The Minister For Fisheries And Management Arrangements For 1992/93, Fisheries Department Of Western Australia

Fisheries Management Papers

The Minister for Fisheries announced the 1992/93 fishing season management arrangements for West Coast Rock Lobster Fishery on 11 August 1992. These arrangements arose as a result of the Minister's consideration of the Rock Lobster Industry Advisory Committee's recommendations outlined in Fisheries Management Paper no.46.

Following this announcement, on 28 August 1992, the Western Australian Fishing Industry Council Sub-Committee on rock lobster submitted a range of alternative management proposals.

The Rock Lobster Industry Advisory Committee (RLIAC) met in Perth on the 9 September 1992 at the request of the Minister for Fisheries to further examine and report on management arrangements.


Influence Of The Ruminant Digestive Process On The Germinability Of Range Forage Species, Mohammed S. Al-Mashikhi May 1993

Influence Of The Ruminant Digestive Process On The Germinability Of Range Forage Species, Mohammed S. Al-Mashikhi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ingestion and dispersal of seeds of desirable species by domestic livestock is potentially important as a range improvement practice, but the passage of seed by livestock has only been studied in a fragmented way, particularly for species adapted to rangelands of western North America. The objectives of this research were to examine the effects of different periods of exposure to in vitro and in vivo digestion processes in cattle on the germinability of several grass species, and determine if the in vitro incubation technique is a good predictor of seed fate following passage through the ruminant digestive tract.

Seeds of …


The West Coast Shark Fishery Draft Management Plan., D. A. Hall Apr 1993

The West Coast Shark Fishery Draft Management Plan., D. A. Hall

Fisheries Management Papers

The main purpose of this report is to advance the development of a scheme of management for the commercial shark fishery off the west coast of Western Australia. There is considerable scientific concern over the biological status of commercially important shark stocks in this region, particularly dusky whaler (Carcharhinus obscura), thickskin (Carcharhinus plumbeus) and whiskery sharks (Furgaelus macki).


The South West Beach Seine Fishery Draft Management Plan., D. A. Hall Apr 1993

The South West Beach Seine Fishery Draft Management Plan., D. A. Hall

Fisheries Management Papers

This paper describes the issues in and outlines a proposal for management of the beach seine fishery between Tim's thicket and Cape Beaufort on the south coast. It also proposes management measures for the fishery utilising small mesh gill nets and hand hauled seine nets in the area inside of the 10 metre depth contour.


Evaluation Of Long Term Changes In The Macrobenthic Community Of The Southern Branch Of The Elizabeth River, Virginia, William S. Hunley Apr 1993

Evaluation Of Long Term Changes In The Macrobenthic Community Of The Southern Branch Of The Elizabeth River, Virginia, William S. Hunley

Biological Sciences Theses & Dissertations

Long-term changes in the macrobenthos of the Southern Branch of the Elizabeth River, Virginia were investigated by comparing the present study of community structure with that described ten years earlier by Hawthorne (1980). The results indicated that dominant organisms remained relatively constant in composition but exhibited considerable fluctuation in density. Differences in diversity and spatial distribution of fauna were also observed relative to the previous decade.

Multivariate statistical analyses indicated the macrobenthos exhibited significant spatial and seasonal patterns. Sediments characterized as silts and clays predominated down river while sandier sediment types were most common farther upriver. The spatial distributions of …


Ribosomal Dna And The Phylogeny Of Frogs, David M. Hills, Loren K. Ammerman, Michael T. Dixon, Rafael O. De Sá Mar 1993

Ribosomal Dna And The Phylogeny Of Frogs, David M. Hills, Loren K. Ammerman, Michael T. Dixon, Rafael O. De Sá

Biology Faculty Publications

Phylogenetic analysis of 1656 aligned sites in the 28S ribosomal RNA gene of frogs supports some of the recently recognized higher groups of anurans but provides counter-support for others. The 28S rDNA data support the monophyly of the recently recognized Pipanura (me- sobatrachians plus neobatrachians), which in turn indicates paraphyly of archaeobatrachians. Me- sobatrachians (pelobatoids plus pipoids), which are either considered paraphyletic or weakly sup- ported as monophyletic in morphological analyses, also receive support as a monophyletic group from the 28S rDNA data. Hyloidea (=Bufonoidea), which is widely recognized but lacks morphological support, receives some molecular support as being monophyletic. …


The Prairie Naturalist Volume 25. No. 1. March 1993 Mar 1993

The Prairie Naturalist Volume 25. No. 1. March 1993

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

CONTENTS

FACTORS AFFECTING BIRD COLONIZATION OF RESTORED WETLANDS ▪ L. M. Hemesath and J. J. Dinsmore

RESPONSE OF DABBLING DUCKS TO EARLY-SPRING PARTIAL DRAWDOWN ON LAKE ERIE MARSHES ▪ T. Z. Riley and T. A. Bookhout

OVER-WATER NESTING BY DUCKS IN NORTHEASTERN SOUTH DAKOTA ▪ . K. L. Solberg and K. F. Higgins

ADDITIONAL MOUNTAIN PLOVER SIGHTINGS IN MONTANA ▪ D. M. Prellwitz

SMALL MAMMALS OF WOODED HABITATS OF THE KONZA PRAIRIE RESEARCH NATURAL AREA, KANSAS ▪ D. W. Kaufman, G. A. Kaufman, and E. …


Geological Field Guide To The Cedar Point Biological Station, Keith County, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian Feb 1993

Geological Field Guide To The Cedar Point Biological Station, Keith County, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian

School of Natural Resources: Faculty Publications

This field guide was produced by staff members of the Conservation and Survey Division of the University of Nebraska originally in 1979 at the request of Dr. Brent Nickol, former Director of the Cedar Point Biological Station. It is an introduction to the geologic history and paleoecology of the Cedar Point area intended for students, staff, and other persons using the camp. This revision has been made some 15 years after the first version to reflect changes in ideas resulting from new data collected during that time.

Users of this guide should take care when studying the rock exposures described …


Aspects Of The Ecology Of The Wood Turtle, Clemmys Insculpta (Leconte), In West Virginia, Allan J. Niederberger Jan 1993

Aspects Of The Ecology Of The Wood Turtle, Clemmys Insculpta (Leconte), In West Virginia, Allan J. Niederberger

Theses, Dissertations and Capstones

An ecological study of the wood turtle, Clemmys insculpta (LeConte), was conducted in West Virginia from May 1991 to March 1993. Population structure at the primary study area (WV #1) was estimated to be 46% juvenile (H-8 yrs. old), 26% female and 28% male. Total population estimate for WV #1 was 337 wood turtles, with an aquatic density of 1,980 turtles per Hectare of river and a terrestrial density of 22.5 turtles per ha of terrestrial habitat. Growth measurements and estimates indicate rapid initial growth tapering off at year 8 and gradually declining through year 16. Males grow slightly faster …


Nebraska Butterflies, Stephen M. Spomer Jan 1993

Nebraska Butterflies, Stephen M. Spomer

University of Nebraska State Museum: Staff and Affiliates, Publications

Nebraska is a crossroads of butterfly diversity. Many species reach their distributional limits in Nebraska. The 100th meridian, which runs through central Nebraska, appears to be a good distributional limit for many species. In short, eastern Nebraska contains butterflies similar or identical to those found in most of the eastern United States, central Nebraska has both eastern and western butterflies, and western Nebraska has a butterfly fauna more like the Rocky Mountains or Black Hills. Over 200 species of butterflies have been recorded in Nebraska, which is a higher number than most of our neighboring states. Some of our butterflies …


An Investigation Of The Host Specificity Of The Brown-Headed Cowbird, Brian D. Peer Jan 1993

An Investigation Of The Host Specificity Of The Brown-Headed Cowbird, Brian D. Peer

Masters Theses

We attempted to determine the factors associated with the lack of parasitism of the Common Grackle (Quiscalus quiscula) by the Brown-headed Cowbird (Molothrus ater). We investigated the breeding phenology of the two species, the responses of colonial- and noncolonial-nesting grackles to female cowbird models, the frequency of artificial egg rejection by grackles, incubation success of cowbird eggs transferred into grackle nests, and the survival rates of cowbirds cross-fostered into grackle nests.

By the time cowbirds began egg-laying at our study sites, 88.5 % of all grackle nests were beyond the point of successful parasitism. Grackles responded …


The Relationship Between Lifespan And Reproduction In The Giant Waterbug (Belostoma Flumineum), Wendy Nixdorf Jan 1993

The Relationship Between Lifespan And Reproduction In The Giant Waterbug (Belostoma Flumineum), Wendy Nixdorf

Masters Theses

The evolutionary significance of senescence and death is poorly understood. Life history theory suggests that the allocation of energy to growth or reproduction is necessarily associated with a decrease in energy available for maintenance of the soma. This study attempted to determine if an investment in reproduction would decrease longevity in the giant waterbug (Belostoma flumineum). Male and female waterbugs were collected from the field as last instar stage nymphs and maintained under controlled laboratory conditions. Individuals were randomly assigned to mating effort treatments, (virgins or breeders with breeding efforts ranging from 1 to >5 times). Following breeding, …


Observations On The Pearl Oyster Fishery Of Kuwait, S. M. Almatar, Kent E. Carpenter, R. Jackson, S. H. Alhazeem, A. H. Alsaffar, A. R. A. Ghaffar, C. Carpenter Jan 1993

Observations On The Pearl Oyster Fishery Of Kuwait, S. M. Almatar, Kent E. Carpenter, R. Jackson, S. H. Alhazeem, A. H. Alsaffar, A. R. A. Ghaffar, C. Carpenter

Biological Sciences Faculty Publications

The pearl oyster fishery of Kuwait was monitored daily from January 1989 to May 1990. Landings of pearl oysters in 1989 totaled 287 tons with a market value of U.S. $1.0 million. Commercial pearls (>3 mm) were estimated to be present in one of every 4200 oysters. Most of the pearl oysters landed were new recruits with hinge lengths between 40-56 mm. There was a curvilinear relationship between total weight and size of oysters (length) and the sex ratio approached 1:1. Spawning occurs throughout the year, with a spat settlement peak in early fall. Over the size range examined …


The Effects Of Crayfish Grazing On Benthic Algal Community Dynamics In Southwestern Lake Michigan, Kristi A. Zenchak Jan 1993

The Effects Of Crayfish Grazing On Benthic Algal Community Dynamics In Southwestern Lake Michigan, Kristi A. Zenchak

Master's Theses

No abstract provided.


Distribution Of The Mole Salamander, Ambystoma Talpoideum (Urodela: Ambystomatidae), In Arkansas With Notes On Paedomorphic Populations, Stanley E. Trauth, Betty G. Cochran, David A. Saugey, William R. Posey Ii, Wesley A. Stone Jan 1993

Distribution Of The Mole Salamander, Ambystoma Talpoideum (Urodela: Ambystomatidae), In Arkansas With Notes On Paedomorphic Populations, Stanley E. Trauth, Betty G. Cochran, David A. Saugey, William R. Posey Ii, Wesley A. Stone

Journal of the Arkansas Academy of Science

No abstract provided.


Do Worm Lizards Occur In Nebraska?, Louis A. Somma Jan 1993

Do Worm Lizards Occur In Nebraska?, Louis A. Somma

Papers in Herpetology

Amphisbaenids, or worm lizards, are a small enigmatic suborder of reptiles (containing 4 families; ca. 140 species) within the order Squamata, which include~ the more speciose lizards and snakes (Gans 1986). The name amphisbaenia is derived from the mythical Amphisbaena (Topsell 1608; Aldrovandi 1640), a two-headed beast (one head at each end), whose fantastical description may have been based, in part, upon actual observations of living worm lizards (Druce 1910). While most are limbless and worm-like in appearance, members of the family Bipedidae (containing the single genus Bipes) have two forelimbs located close to the head. This trait, and …


How Does Variation In Plant Resources Affect Herbivore Dynamics?: Review Of Hunter Et Al., Effects Of Resource Distribution On Animal-Plant Interactions, Svata M. Louda Jan 1993

How Does Variation In Plant Resources Affect Herbivore Dynamics?: Review Of Hunter Et Al., Effects Of Resource Distribution On Animal-Plant Interactions, Svata M. Louda

Svata M. Louda Publications

The book by Hunter et al. has two aims. The first is to focus more attention on the role of variation in resources, specifically plant resources, in the dynamics of herbivorous animals. The emphasis on plant variability in herbivore performance and dynamics, rather than on average patterns of plant resource availability, is timely. Emphasis to date has been on general patterns of resource use. However, knowledge of variation is required to predict outcomes of both ecological processes and evolutionary changes with environmental modification. Thus, I expect this book will be considered an important step on the road to such understanding. …


Effects Of Response Strategy And Retention Interval On Performance Of Clark’S Nutcrackers In A Radial Maze Analogue, Deborah J. Olson, Alan C. Kamil, Russell P. Balda Jan 1993

Effects Of Response Strategy And Retention Interval On Performance Of Clark’S Nutcrackers In A Radial Maze Analogue, Deborah J. Olson, Alan C. Kamil, Russell P. Balda

Papers in Behavior in Biological Sciences

Two groups of Clark’s nutcrackers (Nucifraga columbiana) were trained to use either a stay or shift response strategy in a radial maze analogue. Each trial had a preretention stage, a retention interval, and a postretention test. In Experiment 1, acquisition with a 5-min retention interval was studied. Response strategy did not affect the rate at which the task was learned. Performance following longer retention intervals was tested in Experiments 2-4. Changes in retention intervals were presented in trial blocks of increasing duration in Experiment 2 and were randomly presented between trials in Experiment 3. Experiment 4 extended the …


Spiculopteragia Spiculoptera And S. Asymmetrica (Nematoda: Trichostrongyloidea) From Red Deer (Cervus Elaphus) In Texas, Lora G. Rickard, Eric P. Hoberg, Nancy M. Allen, Gary L. Zimmerman, Thomas M. Craig Jan 1993

Spiculopteragia Spiculoptera And S. Asymmetrica (Nematoda: Trichostrongyloidea) From Red Deer (Cervus Elaphus) In Texas, Lora G. Rickard, Eric P. Hoberg, Nancy M. Allen, Gary L. Zimmerman, Thomas M. Craig

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Specimens of Spiculopteragia spiculoptera and S. asymmetrica were recovered from the abomasa of five of ten naturally infected red deer (Cervus elaphus) in Texas (USA). Female specimens of Spiculopteragia were present in all five animals. Male specimens of S. spiculoptera and S. asymmetrica were present in one of five and three of five red deer, respectively. Spiculopteragia spiculoptera has not previously been recognized in the United States and the present report constitutes the first records of Spiculopteragia spp. in red deer from North America. It is likely that species of Spiculopteragia have been introduced to North America with …


Book Review Of Parascript: Parasites And The Language Of Evolution By D. R. Brooks And D. A. Mclennan, Smithsonian Institution Press, Washington, D.C., 1993., Eric P. Hoberg Jan 1993

Book Review Of Parascript: Parasites And The Language Of Evolution By D. R. Brooks And D. A. Mclennan, Smithsonian Institution Press, Washington, D.C., 1993., Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Review of Parascript: Parasites and the Language of Evolution by Daniel R. Brooks and Deborah A. McLennan, with bibliographical references.


Ecology Of The State Endangered Yellow Mud Turtle, Kinosternon Flavescens In Henry Co., Illinois, Michael W. Tuma Jan 1993

Ecology Of The State Endangered Yellow Mud Turtle, Kinosternon Flavescens In Henry Co., Illinois, Michael W. Tuma

Masters Theses

Illinois populations of the state endangered yellow mud turtle (Kinosternon flavescens) persist in scattered locations on sand prairies. The largest population occurs on a remnant sand prairie of the former Green River Marsh in Henry Co. A study was conducted during 1992 to determine important criteria for preserve design. These criteria included extent of turtle movements within the site and habitat use. Turtles were captured by aquatic hoop traps, drift fence, and by hand from May 11 to August 31. A total of 16 adults, four juveniles, and eight hatchlings were captured. Population size was estimated at 44.80 adults using …


Biotic, Abiotic, And Behavioral Patterns Associated With The Nocturnal Movements Of Shrews, Patrick T. Sullivan Jan 1993

Biotic, Abiotic, And Behavioral Patterns Associated With The Nocturnal Movements Of Shrews, Patrick T. Sullivan

Masters Theses

Thirteen trails left by shrews coated with fluorescent powder were examined for microhabitat documentation. Thirteen data parameters were collected from each trail, two of which differed significantly between Blarina brevicauda and Sorex longirostris. The small soricid Sorex longirostris was captured in areas with higher grass content, and lower wooded content, than the larger Blarina brevicauda. The difference in microhabitat use may be a key mechanism in reducing competition between these two species.


The Effects Of Nest-Box Visibility And Proximity On The Frequency Of Brood Parasitism In Wood Ducks, Roger W. Jansen Jan 1993

The Effects Of Nest-Box Visibility And Proximity On The Frequency Of Brood Parasitism In Wood Ducks, Roger W. Jansen

Masters Theses

I studied the effects of nest box visibility and clustering on the rate of intraspecific brood parasitism (IBP) in Wood Ducks (Aix sponsa) at Lake Shelbyville Fish and Wildlife Area in Moultrie County, IL from 2 March 1992 to 22 June 1992. Sixty-eight percent of the nest boxes sampled were used and 33% of the nests were destroyed by predators. Mean clutch sizes of unparasitized (x = 9.2) and parasitized (x = 15.2) nests were significantly different. The parasitism rate in Wood Duck nests was 54%. More visible boxes had a tendency to be parasitized at a higher rate than …


Growth And Survival Of Larval Fishes: The Role Of Zooplankton Abundance And Competition, Michael T. Welker Jan 1993

Growth And Survival Of Larval Fishes: The Role Of Zooplankton Abundance And Competition, Michael T. Welker

Masters Theses

Interactions among larval gizzard shad, bluegill and zooplankton prey were examined via a controlled mesocosm experiment and field sampling in Lake Shelbyville, Illinois. In the mesocosm experiment gizzard shad growth and survival were negatively correlated with shad density and positively correlated with macrozooplankton prey. Bluegill growth was also positively correlated with prey availability, but survival was uniformly high despite differences in zooplankton abundance and fish density. Declines in macrozooplankton and copepod biomass were related to fish density. In Lake Shelbyville limnetic overlap of larval gizzard shad and bluegill was limited to a three week period, with the interval of greatest …


Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald Jan 1993

Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald

OES Faculty Publications

Benthic microalgal chlorophyll a and production were measured at 3 sites at Stellwagen Bank, a cold temperate continental shelf habitat in Massachusetts Bay, USA, during August 1991. Benthic microalgal chlorophyll a averaged 39.8 Mg M-2, vs average integrated phytoplankton chlorophyll a of 25.9 mg m-2. Gross benthic microalgal production, measured by oxygen exchange in clear and opaque benthic chambers, averaged 20.9 mg C m-2 h-1. This production was supported by average daily light fluxes to the bottom that never exceeded 1 % of surface incident radiation and were as low as 4.7 μE …