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Articles 931 - 960 of 1020

Full-Text Articles in Ecology and Evolutionary Biology

The King George Sound Purse Seine Fishery Working Group Report By The Chairman Mr. R. S. Brown To The Minister For Fisheries., R. S. Brown Nov 1986

The King George Sound Purse Seine Fishery Working Group Report By The Chairman Mr. R. S. Brown To The Minister For Fisheries., R. S. Brown

Fisheries Management Papers

The King George Sound Purse Seine Fishery Working Group was formed to investigate the purse seine (mainly mulie) fishery in King George Sound and advise the Minister for Fisheries on options for future management. The fishery in King George Sound is unlike most fisheries because the fish stock (pilchards) which is exploited is part of a very extensive stock located right around the south and north west coast of Western Australia. Only relatively small portion of the total stock of pilchard enter King George Sound and comes under the very high exploitation there. The Working Group has proposed to the …


The Esperance Rock Lobster Working Group Interim Report By The Chairman Mr. A. Pallot To The Western Australia Fishing Industry., A. Pallot Nov 1986

The Esperance Rock Lobster Working Group Interim Report By The Chairman Mr. A. Pallot To The Western Australia Fishing Industry., A. Pallot

Fisheries Management Papers

In July 1985 the Minister for Fisheries released a discussion paper titled "Arrangements for entry to all fisheries off and along the Western Australian coast" for consideration by all members of the fishing industry. The Australian Fishing Industry Council (W.A. Branch), now the Western Australian Fishing Industry Council (Inc), responded to the discussion paper in March 1986. The following were included in the Council's recommendations: 1. The rock lobster fishery near Esperance be a limited entry fishery. 2. The bench mark date for determining access by April 30, 1985. 3. that the Minister for fisheries establish a representative Government/Industry Working …


The Windy Harbour-Augusta Rock Lobster Working Group. Interim Report By The Chairman Mr. A. Pallot To The Western Australian Fishing Industry., A. Pallot Nov 1986

The Windy Harbour-Augusta Rock Lobster Working Group. Interim Report By The Chairman Mr. A. Pallot To The Western Australian Fishing Industry., A. Pallot

Fisheries Management Papers

Summary of Recommendations: Boat Access: That the Windy Harbour-Augusta Rock Lobster Fishery be declared a limited entry fishery. That the limited entry fishery related to the taking of Western Rock Lobster (Panulirue cygnus) and Southern Rock Lobster (Jasus novaehollandiae) That the southern boundary of Zone E of the W.C.R.L.F. terminate at a point where it intersects with a line drawn in a southerly direction from the Cape Leeuwin lighthouse. That the eastern boundary remain at Point D'Entrecasteaux (approximately 1160east longitude). That the western and southern boundaries by limits of the Australian Fishing Zone. That the season be for the period …


The Report Of The Fish Farming Legislative Review Committee., P. Rogers Oct 1986

The Report Of The Fish Farming Legislative Review Committee., P. Rogers

Fisheries Management Papers

In 1975, amendments to the Fisheries Act provided for the licensing and control of commercial fish farming activities and , for specific declared species, further controls on their processing and marketing. To date, marron has been the only species to be declared a "farm fish". During the last decade, much of the State's aquaculture impetus has focused on marron although more recently greater attention has been directed towards trout, yabbies and freshwater aquarium fish species. On November 19, 1984, the Marron Growers Association of Western Australia (Inc) wrote to the Minister for Fisheries and Wildlife, seeding a general review of …


The Report Of The Southern Western Australian Shark Working Group., P. Millington Apr 1986

The Report Of The Southern Western Australian Shark Working Group., P. Millington

Fisheries Management Papers

The southern Western Australian Shark Working Group was formed to investigate the southern shark fishery and advise the Minister for Fisheries on options for future management. Membership comprised six fishermen from regional professional fishermen's associations and two Fisheries Department officers. The Working Group considered that each shark fisherman obtaining an entitlement should then be restricted in the length of fishing gear he can use and the number of months he can fish. The individual's time and gear entitlement would be approximately that length of gear being used and time spent fishing in a period shortly before the bench mark date. …


A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson Nov 1984

A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson

Publications (WR)

Several limnological studies have been conducted in Lake Mead during the past decade. The recent studies clearly show that most of Lake Mead is deficient in nutrients, especially phosphorus, and very low in productivity. The reservoir-wide average total phosphorus concentration for 1981 - 1982 was only 9 mg/m3. This is below levels found In most oligotrophic lakes and reservoirs. Algal biomass, as measured by chlorophyll-a, averaged only 1.5 mg/m3. That also places Lake Mead in the oligotrophic range. Transparency, as measured by a Secchi disc, averaged 9-5 m in Lake Mead during 1981-1982. That far exceeds …


Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde May 1984

Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde

Publications (WR)

Zooplankton samples collected from throughout Lake Mead, in 1981-1982, demonstrate the presence of a statistically significant seasonal and spatial heterogeneity in zooplankton densities. Seasonally, the major zooplankton groups were most abundant in the spring and fall, coincident with maxima in chlorophyll-a concentrations. Successions among the various rotifers, cladocerans and copepods present in the reservoir were influenced by food availability, diapause, predation by planktivorous fish and, possibly, water temperatures. Spatial heterogeneity in zooplankton densities was unrelated to water temperature, pH, conductivity and dissolved oxygen concentrations, but was related to the abundance of phytoplankton (chlorophyll-a concentrations) and fish. Statistical analyses indicate that …


Effects Of Commercial Fish Removal On Sport Fish Populations In Two Arkansas Reservoirs, Tommie Crawford Jan 1984

Effects Of Commercial Fish Removal On Sport Fish Populations In Two Arkansas Reservoirs, Tommie Crawford

Journal of the Arkansas Academy of Science

Commercial netting occurred October through April, 1971-1976 on Nimrod Lake and from October through April, 1973-1977 on Blue Mountain Lake in west central Arkansas. Using 7.6 cm or larger mesh gill and/or trammel nets, commercial fishermen harvested commercial fishes (buffalofishes [Ictiobus spp.]; common carp [Cyprinus carpio], carpsuckers [Carpiodes spp.]; drum [Aplodinotus grunniens]; gars [Lepisosteus spp.]; suckers [Catostomidae); and catfishes [Ictalurus spp. and Pylodictis olivaris]). During the study period, cove rotenone samples were conducted on an annual basis. Fishes collected were placed into age classes and enumerated. Data were then grouped into general categories (black basses [Micropterus spp], crappie [Pomoxis spp.], …


Temperature Preference And Tolerance Of Grass Carp (Ctenopharyngodon Idella), Marvin L. Galloway, Raj V. Kilambi Jan 1984

Temperature Preference And Tolerance Of Grass Carp (Ctenopharyngodon Idella), Marvin L. Galloway, Raj V. Kilambi

Journal of the Arkansas Academy of Science

Grass carp, acclimated at 24 °C, were tested for temperature preference in a laboratory, horizontal gradient tank. After a 6-day period of exploration the grass carp gravitated to a final thermal preferendum of 35 °C. In the temperature tolerance test the ultimate upper incipient lethal temperature (TL50), was estimated as 41.5°C. The results are compared to those of a similar study with hybrid carp (female grass carp x male bighead carp).


Avoidance Learning And Memory In Largemouth Bass (Micropterus Salmoides) Fed Bufo Tadpoles, Randy John Gawlik Jan 1984

Avoidance Learning And Memory In Largemouth Bass (Micropterus Salmoides) Fed Bufo Tadpoles, Randy John Gawlik

Masters Theses

Tadpoles of the American toad (Bufo americanus) have been shown to be distasteful to largemouth bass (Micropterus salmoides) predators who learn, on the short term, to avoid them. How long bass retain this learned avoidance of Bufo larvae is unknown so an experimental design was constructed in an attempt to answer this question.

Largemouth bass were divided into four treatment groups. Two groups were initially fed exclusively larvae of Bufo americanus (one group was fed large tadpoles, the other group fed small larvae). Similarily, the other two groups were initially fed spring peeper (Hyla crucifer …


Factors Affecting Reproductive Success Of Bonytail Chubs And Razorback Suckers In Lake Mohave, Michael A. Bozek, Larry J. Paulson, James E. Deacon, U.S. Department Of Interior, Fish And Wildlife Service Jan 1984

Factors Affecting Reproductive Success Of Bonytail Chubs And Razorback Suckers In Lake Mohave, Michael A. Bozek, Larry J. Paulson, James E. Deacon, U.S. Department Of Interior, Fish And Wildlife Service

Publications (WR)

Razorback suckers (Xyrauchen texanus) and bonytail chubs (Gila elegans) were once widespread throughout the Colorado River system. The ranges and populations of these native species and others have declined in the past 50 years. Bonytail chubs appear to be extremely rare and possibly nearing extinction in the Upper Colorado River Basin. The razorback sucker is widely distributed in the upper river but is considered rare throughout most of that range and is also rare in the Grand Canyon. Razorback suckers are abundant only in a few habitats in the upper river. They congregate and spawn over …


A Checklist Of Parasites Of California, Oregon, And Washington Marine And Estuarine Fishes, Milton S. Love, Mike Moser Dec 1983

A Checklist Of Parasites Of California, Oregon, And Washington Marine And Estuarine Fishes, Milton S. Love, Mike Moser

Harold W. Manter Laboratory of Parasitology: Faculty Publications

This report is a summary of the published records of parasites found from the marine and estuarine fishes of California, Oregon, and Washington. Coverage has not been limited to the western United States, but rather includes parasite reports from throughout each fish's range. Included is a host-parasite list and parasite-host cross index.

We have produced this survey because we felt there was a need for a single source which would list all the parasites infecting marine and estuarine fish from California, Oregon, and Washington. Pertinent sources are scattered over a number of journals, covering many years. Workers find it time …


The Effect Of Crowding On Growth Of The Cichlid Fish, Oreochromis Mossambicus, Bonnie A. Barrows Jul 1983

The Effect Of Crowding On Growth Of The Cichlid Fish, Oreochromis Mossambicus, Bonnie A. Barrows

OES Theses and Dissertations

It has been reported that the Java tilapia, Oreochromis mossambicus, displays hypersensitivity to a substance it produces when biomass levels in a flow-through culture system exceed 20 g/1, resulting in reduced growth and high mortality. Experiments on the growth of this species in small tanks were conducted in order to determine whether O. mossambicus produces a growth-inhibiting compound under crowded conditions. This species was successfully maintained at biomass levels of 38 g/1 and 57 g/1 with a total mortality of only 4.5%.

The Java tilapia can grow rapidly in small aquaria, as indicated by the data taken during Experiment …


A Survey Of The Aspidogastrean And Hydracarine Parasites Of Bivalue Molluscs In Western West Virginia, Donald W. Danford Jan 1983

A Survey Of The Aspidogastrean And Hydracarine Parasites Of Bivalue Molluscs In Western West Virginia, Donald W. Danford

Theses, Dissertations and Capstones

Aspidogaster conchicola and Cotylaspis insignis were only two aspidogastrid trematodes recovered in a year long study involving 500 bivalves (22 species) collected from a thirteen county area in western West Virginia. Also collected were three species of aquatic mites identified as: Union­ icola fossulata, Unionicola formosa, and Najadicola ingens. Only ten species of mussels were infested with trematodes: Pleurabema cordatum (100%); Anodonta grandis (70% for A•conchicola, 60% for Q. insignia); Potamilus alata (50%); Tritogonia verrucosa (46%); Strophitus undulatus (6.25%); guadrula guadrula (33%); Amblema plicata (31%); guadrula postulosa (50%); Lampsilis ventricosa (7.11%); Lampsilis radiata luteola (7.12% for A. conchiocola, 10.2% for …


Spawning The Grass Carp Female X Bighead Carp Male, Mike Freeze, Scott Henderson Jan 1983

Spawning The Grass Carp Female X Bighead Carp Male, Mike Freeze, Scott Henderson

Journal of the Arkansas Academy of Science

Methods and procedures for artificially spawning the female grass carp (Ctenopharyngodon idella) X male bighead carp (Aristichthys nobilis) are presented. Broodstock selection and treatment, hormone injections, ovulation, fertilization, hatching techniques and stocking rates are discussed. This paper outlines the procedures necessary to successfully produce hybrid grass carp


Comparison Of Two Year Classes Of Hybrid Grass Carp And Grass Carp For Aquatic Plant Control, Mike Freeze, Scott Henderson Jan 1983

Comparison Of Two Year Classes Of Hybrid Grass Carp And Grass Carp For Aquatic Plant Control, Mike Freeze, Scott Henderson

Journal of the Arkansas Academy of Science

Two year classes of grass carp and F, hybrids resulting from bighead carp male x grass carp female were compared at various stocking densities for aquatic plant control. One and two year old grass carp exhibited higher survival rates and better growth rates than the same age hybrid grass carp. The presence of grass carp or hybrid grass carp decreased both Secchi disc transparencies and dissolved oxygen values. Grass carp had a greater negative effect upon these measurements because they removed the vegetation quicker than the hybrid grass carp. These apparent detrimental effects on water quality are necessary trade-offs for …


Observed Changes In The Largemouth Bass Population Since Construction Of A New Pump Storage Reservoir At Charleston, Illinois, Lawrence B. Durham Jan 1983

Observed Changes In The Largemouth Bass Population Since Construction Of A New Pump Storage Reservoir At Charleston, Illinois, Lawrence B. Durham

Masters Theses

Lake Charleston, Illinois was electrofished to determine the status of the largemouth bass (Micropterus salmoides, Lacepede) population after its reconstruction into a pump storage reservoir. The changes observed were an increased rate of growth of the initial year class, increased average growth increment of older bass, and a more abundant bass population. Factors which may have influenced increased growth were decreased turbidity, alkalinity, and increased water level. There is a possibility the increase in water level led to an increase in terrestrial invertebrates as a food source, and increased spawning substrate and cover due to submerged terrestrial vegetation. …


The Ecology Of The Mottled Sculpin, Cottus Bairdii, In The Clearwater River, Beltrami County, Minnesota, Mark A. Hanson Aug 1982

The Ecology Of The Mottled Sculpin, Cottus Bairdii, In The Clearwater River, Beltrami County, Minnesota, Mark A. Hanson

Biology Graduate Theses

No abstract provided.


The Influence Of Habitat Variation On The Morphology And Physiology Of Plethodon Wehrlei (Fowler And Dunn) In West Virginia, Sharon Kay Gross Jan 1982

The Influence Of Habitat Variation On The Morphology And Physiology Of Plethodon Wehrlei (Fowler And Dunn) In West Virginia, Sharon Kay Gross

Theses, Dissertations and Capstones

High elevation, low elevation and cave populations of Plethodon wehrlei (Fowler and Dunn) in West Virginia were compared to determine the influence of habitat variation on morphology and physiology. Discriminant analysis of 14 external morphological characters and 11 skeletal characters revealed a similar morphology for the three populations. Comparisons of critical thermal maxima showed a positive correlation to habitat temperature. Dehydration studies revealed that the high elevation population was more resistant and tolerant to water loss than the cave and low elevation populations.


A Distributional And Taxonomic Study Of The Adults Of The Family Hydropsychidae (Trichoptera) In West Virginia, Toni Ann Phillips Jan 1982

A Distributional And Taxonomic Study Of The Adults Of The Family Hydropsychidae (Trichoptera) In West Virginia, Toni Ann Phillips

Theses, Dissertations and Capstones

A survey of the adult Hydropsychiclae revealed 39 species, 14 of which were state records. The adult hydropsychids were collected from various locations throughout West Virginia. The most common species Hydropsychidae were Hydropsyche morosa, H. sparna, Cheumatopsyche analis, C. campyla, and Diplectrona modesta. Most of the species did not appear to be limited to any one particular drainage basin. Several species exhibited a preference for stream order (headwaters, middlereaches, large rivers). Aphropsyche monticola, Parapsyche apicalis, Cheumatopsvche wrighti, C, gyra, and Hydropsyche alhedra preferred the fast-flowing headwater streams in the higher elevations of the state. Macrostemum zebratum, Potomyia flava, Hydropsyche phalerata, …


Effects Of Water Released From Stratified And Unstratified Reservoirs On The Downstream Water Quality, Stephen B. Smith Jan 1982

Effects Of Water Released From Stratified And Unstratified Reservoirs On The Downstream Water Quality, Stephen B. Smith

Journal of the Arkansas Academy of Science

Water quality samples were collected from the Little River system in Pine Creek Lake, Oklahoma, and Gillham Lake, Arkansas, and their associated tailwaters during the winter (reservoirs unstratified) and summer (reservoirs stratified) of 1980. Downstream water quality was not affected by reservoir water releases while the reservoirs were unstratified. When the reservoirs were stratified water quality in the tailwaters was dependent on the release depth of the water. The practice of flushing out a tailwater following an extended low flow period should be examined on a site by site basis. Anoxic water released from a reservoir may contain high amounts …


Evaluation Of Instream Flow Methodologies For Fisheries In Nebraska, Phil Hilgert Jan 1982

Evaluation Of Instream Flow Methodologies For Fisheries In Nebraska, Phil Hilgert

Nebraska Game and Parks Commission: Publications

Five instream flow methods were applied to a variety of streams within the state of Nebraska. These were (1) the Tennant method, (2) a modification of the Tennant method, (3) IFG1 A, a single cross-section average-parameter method, (4) the Incremental method, using the WSP hydraulic simulation program, and (5) the Incremental method, using the IFG4 hydraulic simulation program.

Each method was applied following standard published procedures, and instream flow recommendations were developed for the streams addressed using each method separately. Evaluation of the methods showed that the modification of the Tennant method overcame some of the deficiencies of the Tennant …


Warmwater Fish Community Of A Cool Tailwater In Arkansas, Richard A. Frietsche Jan 1982

Warmwater Fish Community Of A Cool Tailwater In Arkansas, Richard A. Frietsche

Journal of the Arkansas Academy of Science

A diverse warmwater fish community has persisted in the Lake Greeson tailwater, despite hydropower releases of cold hypolimnetic water. Forty-eight species of fish were collected by electrofishing in the upper 16.1 km of the tailwater. Hydropower releases have reduced the abundance of some of the warmwater sport fish in the upper tailwater, and their populations are probably maintained in part by recruitment from downstream. Angling effort has been diverted from the warmwater sport fish populations to a put-and-take trout fishery.


Water Quality And Benthic Invertebrate Communities In Lake Greeson Tailwater, Stephen B. Smith Jan 1982

Water Quality And Benthic Invertebrate Communities In Lake Greeson Tailwater, Stephen B. Smith

Journal of the Arkansas Academy of Science

The Little Missouri River below Lake Greeson, Arkansas, was sampled for water quality and benthos during summer 1979. The hydropower turbine water intakes, 20 m below the lake surface, released hypolimnetic water into the tailwater. Downstream water temperatures, total organic matter, and total inorganic matter varied considerably and benthic invertebrate communities immediately below the dam were stressed by waters released for power generation. Detrimental effects from altered temperature and flow regimes had decreased by 16.1 km downstream, where invertebrate communities were typical of less stressed environments.


The Seasonality Of Occurrence Of Larval And Juvenile Sciaenids In A Virginia Seaside Estuary, James Howard Cowan Jr. Jul 1981

The Seasonality Of Occurrence Of Larval And Juvenile Sciaenids In A Virginia Seaside Estuary, James Howard Cowan Jr.

Biological Sciences Theses & Dissertations

The seasonality of occurrence and relative abundance of larval and juvenile fishes, particularly members of the family Sciaenidae, from a Virginia seaside estuary were determined from ichthyoplankton and trawl collections made from March 1979 to March 1980.

The larvae of 20 species distributed among 15 families were identified from the ichthyoplankton. Larvae of the bay anchovy, Anchoa mitchilli, and the Atlantic silverside, Menidia menidia, dominated the samples and made up 57 and 34%, respectively, of all larvae collected. Peak occurrence began in May and continued through August. Fish larvae were present in the study area all year.

Twenty-eight …


Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat May 1981

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …


A Survey Of The Mussels (Pelecypoda: Unionoidia: Unionacea) Of Twelvepole Creek, West Virginia With A Study Of Commensal Algae Found On Selected Mussels, Kevin Joe Smith Jan 1981

A Survey Of The Mussels (Pelecypoda: Unionoidia: Unionacea) Of Twelvepole Creek, West Virginia With A Study Of Commensal Algae Found On Selected Mussels, Kevin Joe Smith

Theses, Dissertations and Capstones

A survey of the Unionacea of Twelvepole Creek, West Virginia was conducted coupled with a qualitative study of commensal algae found on selected mussel species. The naiads and the algae were found to have diverse populations. Naiads collected during the survey were represented by 23 species, 16 genera and 2 families. Corbicula fluminea was found to be confined largely to the main branch of Twelvepole, with no individuals being collected from the East or West Forks and only limited collections near the mouth of Beechfork Creek. Lampsilis radiata luteola and L. ventricosa were found to have the greatest distribution, being …


The Naiads (Mollusca: Unionidae) From Two Prehistoric Sites Along The Ohio River, Mason County, West Virginia, Beverly Dawn Spurlock Jan 1981

The Naiads (Mollusca: Unionidae) From Two Prehistoric Sites Along The Ohio River, Mason County, West Virginia, Beverly Dawn Spurlock

Theses, Dissertations and Capstones

Archeological naiad valves representing 29 species were recovered from two Late Prehistoric Indian villages along the Ohio River, Mason County, West Virginia. Surface collections and limited excavation provided a total of 1,599 identifiable valves and valve fragments. Dif­ferences in species compositions and relative abundances between the two middens were noted. Samples from the Rolf Lee Farm Site (46MS51) contained 28 species while the Lewis-Old Town Farm Site (46MS57) produced only 23 species. Comparisons were made with other nearby prehistoric shell deposits and also with more recent twentieth century collections from this reach of the river. Nine of the archeological species …


Food Habits Of Largemouth Bass, Micropterus Salmoides (Lacepede) And Spotted Bass, Micropterus Punctulatus (Rafinesque), From Beech Fork Reservoir, A New Impoundment In Wayne And Cabell Counties, West Virginia, Michael A. Arcuri Jan 1981

Food Habits Of Largemouth Bass, Micropterus Salmoides (Lacepede) And Spotted Bass, Micropterus Punctulatus (Rafinesque), From Beech Fork Reservoir, A New Impoundment In Wayne And Cabell Counties, West Virginia, Michael A. Arcuri

Theses, Dissertations and Capstones

A study was undertaken to determine the food habits of two game fishes, the largemouth bass Micropterus salmoides (Lacepede) and the spotted bass M. punctulatus (Rafinesque) in Beech Fork Reservoir shortly after its impoundment. A total of 171 largemouth bass and 95 spotted bass were collected from July 1978, through June 1979, and their stomach contents analyzed.

Largemouth bass fed primarily on fishes, particularly young-of-the-year bluegill. Aquatic and terrestrial invertebrates were also important food items, especially during the spring and fall . The dominant aquatic forms were chironomid larvae and pupae while the dominant terrestrial forms were adult dipterans.

Spotted …


Tornadoes West Of The Divide: A Climatology, Richard P. Mcnulty Jan 1981

Tornadoes West Of The Divide: A Climatology, Richard P. Mcnulty

National Oceanographic and Atmospheric Administration: Technical Reports and Related Materials

A climatology of tornado occurrence west of the Continental Divide is presented. These tornadoes are a small but significant part of severe weather occurrences over the United States. Data are examined from both the spatial and temporal point of view. The influence of population and topography is highly evident.