Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
Relative Abundance ◽  
Mississippi River ◽  
Low Frequency ◽  
Catch Per Unit Effort ◽  
High Quality ◽  
Study Objective ◽  
Conservation Ecology ◽  
Flathead Catfish ◽  
Baseline Information ◽  
Catch Statistics

<em>Abstract</em>.—Flathead catfish <em>Pylodictis olivaris</em> are native to Missouri and comprise one of the most important recreational and commercial fisheries in Missouri. Our specific study objective was to describe catch statistics for flathead catfish populations in moderate-large rivers in Missouri to provide sampling guidance for fisheries managers where a paucity of information existed. We used low-frequency (15 Hz) DC electrofishing and hoop nets in segments of the Grand, Lamine, and Platte rivers and pools 20–22 of the upper Mississippi River (UMR) during April–July 2006–2007. Electrofishing mean catch per unit effort (CPUE) ranged from 13.1 (Lamine) to 116.6 (UMR) fish/h while hoop-net mean CPUE ranged from 0.131 (Lamine) to 0.694 (Grand) fish/hoop-net-night. Length distributions showed that hoop nets caught a higher relative abundance of flathead catfish over 40 cm total length (TL) compared to electrofishing, most notably in the Grand and Platte rivers, whereas electrofishing caught relatively more flathead catfish under 35 cm TL in all rivers compared to hoop nets. Our results indicate that a combination of low-frequency (15 Hz) electrofishing and hoop nets should be used during the period of April 15 through July 15 to best represent length structure and relative abundance of flathead catfish populations in these rivers. More specifically, we found low-frequency electrofishing to be most effective for stock size and larger flathead catfish during mid-April to mid-June; however, these results were not as conclusive in 2007. As popularity and angling pressure of these fisheries increases, our results will provide managers with sampling guidance and baseline information in efforts to develop high-quality flathead catfish populations in selected rivers.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
Population Dynamics ◽  
Channel Catfish ◽  
Mississippi River ◽  
Upper Mississippi River ◽  
Catch Per Unit Effort ◽  
Blue Catfish ◽  
Resource Monitoring ◽  
Flathead Catfish ◽  
Unit Effort ◽  
Catch Rates

<em>Abstract</em>.—Using Long Term Resource Monitoring Program data collected from impounded (Pool 26) and unimpounded (Open River) reaches of the upper Mississippi River, we investigated population dynamics of flathead catfish <em>Pylodictis olivaris</em>, channel catfish <em>Ictalurus punctatus</em>, and blue catfish <em>I. furcatus</em> from random sites located in side channel border (SCB) and main channel border (MCB) habitats. Objectives were to (1) compare trends (1993–2007) of three catfishes collected in Pool 26 and Open River reaches of the upper Mississippi River, and (2) provide needed information to managers on population dynamics through time using a binary gear approach of active (i.e., daytime electrofishing) and passive gears (hoopnetting). Active gears resulted in a higher catch per unit effort (CPUE) of all catfishes in each habitat–reach combination as compared to passive gears. Passive gears resulted in negligible catches of blue catfish and flathead catfishes (e.g., mean of <1 fish/net night). Catch per unit effort using active gear resulted in a greater number of channel catfish captured in Pool 26 compared to the Open River, with Open River SCB habitat having the lowest CPUE in most years. Blue catfish in the Open River had a higher CPUE using active gear as compared to Pool 26, with the Open River MCB having the greatest CPUE. Flathead catfish had a higher CPUE in MCB habitat compared to SCB habitat, with the Open River MCB having the highest CPUE in most years. However, declining trends in flathead catfish appears to be occurring in Open River habitats while trends in flathead catfish appear to be slightly increasing in Pool 26. The most common length-classes captured were substock and stock-sized fish regardless of habitat, species, or reach. Trends for channel catfish were easily determined due to high catch rates; however, more monitoring and enhanced sampling is needed to accurately assess flathead catfish and blue catfish trends and to accurately determine demographics for all three species.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Body Condition ◽  
Relative Abundance ◽  
Habitat Restoration ◽  
Missouri River ◽  
Natural State ◽  
Pylodictis Olivaris ◽  
Conservation Ecology ◽  
Flathead Catfish ◽  
Growth Increments

<em>Abstract</em>.—An assessment of the flathead catfish <em>Pylodictis olivaris</em> population in the Missouri River bordering Nebraska was conducted between 1997 through 2008. The Missouri River was divided into four sections based on physical and geomorphologic uniqueness (upper unchannelized, lower unchannelized, upper channelized, and lower channelized). Two sections were sampled annually, and each section was sampled on alternate years. Boat electrofishing collected 12,846 fish in 83.5 h from 701 sampling stations. Most flathead catfish sampled (98%) were less than 510 mm total length (quality length), with significantly more fish captured in channelized than unchannelized reach. Fish from channelized sections also had higher mean total lengths and larger growth increments but were in poorer body condition than those from unchannelized sections. Low relative abundance of flathead catfish in the upper unchannelized section and scarcity of large individuals were attributed to poor habitat conditions. Habitat restoration along with restoring natural riverine processes would return the river to a more natural state and would not only benefit flathead catfish, but other native Missouri River fishes as well.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
Mississippi River ◽  
Age Estimation ◽  
Fish Population ◽  
High Variability ◽  
Annual Growth ◽  
Age And Growth ◽  
Large Fish ◽  
Conservation Ecology ◽  
Flathead Catfish ◽  
Actual Growth

<em>Abstract</em>.—Characterizing dynamics of a fish population requires accurate age estimation for individual fish, and few studies have collected basic age and growth information for flathead catfish in the upper Mississippi River (UMR). Multiple methods were used to calculate age and growth of flathead catfish from the UMR. Length at age was determined using sectioned otoliths and pectoral spines cut on the articulating process. Most research has shown that otoliths provide the most accurate age when compared to other structures. Otoliths require sacrifice of many fish, including very large fish (i.e.: >762 mm). Otoliths and pectoral spines were collected from commercially harvested flathead catfish from Pools 12 and 13 (river kilometer [rkm] 841.0–938.3), UMR, aged and compared. Growth was similar between genders, and there was little difference in growth predicted by the two aging structures. Spine articulating processes and otoliths both showed high variability in growth starting at age 1. When we compared the two structures, the spine articulating process accurately aged fish up to 17 years old (mean total length = 907 mm) before loss of annuli occurred. Aging flathead catfish with the spine articulating process provides an accurate, reliable, affordable, nonlethal aging technique that may be preferable in many situations as opposed to otoliths. Annual and seasonal growth was calculated from flathead catfish captured from Pool 13 (rkm 841.0–895.9), UMR, tagged with a visual implant tag and subsequently recaptured. Actual growth over the summer was estimated to be 0.25 mm/d, and growth from year to year was estimated to be 32 mm/year. The actual annual growth (31.9 mm/year) calculated from tag returns validates estimates of annual growth derived from otolith (30.2 mm/year) and spine articulating process (31.0 mm/ year) aging techniques.

Ecological and environmental factors affecting the foraging activity of the White-bellied Heron Ardea insignis (Hume, 1878) in Bhutan

2021 ◽  
pp. 1-18
Author(s):  
PEMA KHANDU ◽  
GEORGE A. GALE ◽  
SARA BUMRUNGSRI
Keyword(s):  
Relative Abundance ◽  
Habitat Restoration ◽  
Prey Species ◽  
Catch Per Unit Effort ◽  
Factors Affecting ◽  
Prey Biomass ◽  
Gravel Mining ◽  
Unit Effort ◽  
Prey Preferences ◽  
The Government

Summary White-bellied Heron Ardea insignis (WBH) is critically endangered, but we lack data on many aspects of its basic ecology and threats to the species are not clearly understood. The goal of this study was to analyse WBH foraging microhabitat selection, foraging behaviour, and prey preferences in two river basins (Punatsangchhu and Mangdechhu) in Bhutan which are likely home to one of the largest remaining populations of WBH. We also explored the relationship between the relative abundance of the WBH and prey biomass catch per unit effort within four foraging river microhabitats (pool, pond, riffle and run). Prey species were sampled in 13 different 100-m thalweg lengths of the rivers using cast nets and electrofishing gear. Riffles and pools were the most commonly used microhabitats; relative abundance was the highest in riffles. The relative abundance of WBH and prey biomass catch per unit effort (CPUE) also showed a weak but significant positive correlation (rs = 0.22). The highest biomass CPUE was observed in riffles while the lowest was found in the ponds. From the 97 prey items caught by the WBH, 95% of the prey were fish. The WBH mainly exploited three genera of fish (Garra, Salmo, and Schizothorax) of which Schizothorax (64%) was the most frequently consumed. This study provides evidence in support of further protection of critical riverine habitat and fish resources for this heron. Regular monitoring of sand and gravel mining, curbing illegal fishing, habitat restoration/mitigation, and developing sustainable alternatives for local people should be urgently implemented by the government and other relevant agencies. Further study is also required for understanding the seasonal variation and abundance of its prey species in their prime habitats along the Punatsangchhu and Mangdechhu basins.

scholarly journals 125 Short Duration Monoballismus

CNS Spectrums ◽  
2018 ◽  
Vol 23 (1) ◽  
pp. 79-80
Author(s):  
Davinder Dhillon ◽  
Priya Batta ◽  
Alan R. Hirsch
Keyword(s):  
Short Duration ◽  
Parietal Lobe ◽  
Focal Epilepsy ◽  
Memory Loss ◽  
Low Frequency ◽  
Normal Animal ◽  
Conversion Disorder ◽  
Huntington's Chorea ◽  
Study Objective ◽  
Alien Hand Syndrome

AbstractStudy ObjectiveWhile monoballismus has been reported to be associated with hemorrhagic lesions in the subthalamic nucleus (Ohnishi, 2009) and multiple sclerosis (MS) (Rosa, 2011), the duration has been reported to be at least six days (Soysal, 2012). A patient with epochs of monoballismus lasting for 45 minutes is presented.MethodsCase Study: A 57 year old right handed female with attention deficit hereditary disorder predominantly inattentive on amphetamine sulphate, presented with two years of memory loss. For instance, after ordering food in restaurants, by the time the food arrives, she could not recall what she ordered. At the onset of this symptom, she noted three epochs of her left arm jerking for 45 minutes. The jerking would begin with low amplitude and low frequency and rapidly progress to the forearm and arm of greater magnitude and low frequency. With her right hand she would try to hold down her left arm without success. There was no associated paresis, sensory phenomena, headaches, dizziness, presyncope, loss of consciousness, or strong emotions. She admitted to frequent jamais vu.ResultsAbnormalities: Neurological Examination: Mental Status Examination: Memory: Immediate Recall: 5 digits forward and 2 digits backwards. Cranial Nerve (CN) Examination: CN I: Alcohol Sniff Test 8 (hyposmia). CN XII: tongue tremor on protrusion. Motor Examination: Drift Test: positive right pronator drift. Gait Examination: Tandem Gait: unstable. Reflexes: 0-1 throughout. Neuropsychiatric Examination: Go-No-Go Test: 6/6 (normal). Animal Fluency Test: 15 (normal). Clock Drawing Test: 3 (abnormal). Center for Neurologic Study Lability Scale: 16 (pseudobulbar affect). Other: MRI with and without infusion: normal.ConclusionTransient tonic-clonic movements of one limb have been described with focal epilepsy associated with diabetic non-ketotic hyperglycemia (Grant, 1985). A metabolic abnormality such as transient hypoglycemia or hyperkalemia can cause a focal dystonia (Soysal, 2012), which theoretically could manifest with monoballismus. This could be a somatic manifestation of underlying conflict, conversion disorder, or as a result of a physical manifestation of panic attack with hyperventilation and tetany (Mihai, 2008). This may be the first manifestation of a generalized cerebral disorder associated with chorea or ballismus such as Wilson’s disease, or Huntington’s Chorea (Mihai, 2008). It is possible that this is a variant of Alien Hand Syndrome with parietal lobe involvement (Shrestha, 2015). But this is unlikely given the absence of hemineglect or hemiagnosia. It is possible that amphetamines may have induced a monochorea. Chronic amphetamine use has been demonstrated to cause chorea (Klawans, 1974) and it theoretically could have caused ballismus movements in this case. In patients who present with short duration monoballismus, evaluation for subthalamic nuclei function, seizure disorders and other origins of ballismus are warranted.Funding AcknowledgementsSmell & Taste Treatment and Research Foundation

scholarly journals Standardizing catch rates: is logbook information by itself enough?

2008 ◽  
Vol 65 (2) ◽  
pp. 255-266 ◽  
Author(s):  
J. Bishop ◽  
W. N. Venables ◽  
C. M. Dichmont ◽  
D. J. Sterling
Keyword(s):  
Relative Abundance ◽  
Prediction Models ◽  
Expert Knowledge ◽  
External Information ◽  
Linear Regression Models ◽  
Catch Per Unit Effort ◽  
Estimation Model ◽  
Catch Rates ◽  
Logbook Data ◽  
Estimation Models

Abstract Bishop, J., Venables, W. N., Dichmont, C. M., and Sterling, D. J. 2008. Standardizing catch rates: is logbook information by itself enough? – ICES Journal of Marine Science, 65: 255–266. The goal of the work was to maximize the accuracy of standardized catch per unit effort as an index of relative abundance. Linear regression models were fitted to daily logbook data from a multispecies penaeid trawl fishery in which within-vessel changes in efficiency are common. Two model-fitting strategies were compared. The predictive strategy focused on maximizing the explained variance, and the estimation strategy on finding realistic coefficients for important components of changing catchability. Realistic values could not always be obtained, because the regression factors were not orthogonal, and data on the presence of technology were sometimes unreliable or systematically incomplete. It was not possible to separate fishing power from abundance by analysing logbook data alone; it was necessary to incorporate external information within the standardization model. Therefore, the resultant estimation models incorporated external information and expert knowledge by offsets. There was no single best estimation model. Instead, a series of models provided an envelope of possible changes in relative fishing power and prawn abundance since 1970. Compared with the prediction models, the estimation models revealed different trends in relative fishing power and relative abundance.

scholarly journals Factors affecting relative abundance of low-mobility fishing resources: spiny lobster in the Galapagos Marine Reserve

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7278 ◽  
Author(s):  
Juan Carlos Murillo-Posada ◽  
Silvia Salas ◽  
Iván Velázquez-Abunader
Keyword(s):  
Monitoring System ◽  
Relative Abundance ◽  
Spatial Scales ◽  
Marine Reserve ◽  
Spiny Lobster ◽  
Fishing Effort ◽  
Additive Models ◽  
Catch Per Unit Effort ◽  
Monthly Basis ◽  
Galapagos Marine Reserve

Management of low-mobility or benthic fisheries is a difficult task because variation in the spatial distribution and population dynamics of the resources make the monitoring and assessment of these fisheries challenging. We assumed that environmental, spatial, and temporal factors can contribute to the variability of the relative abundance of such species; we used Generalized Additive Models for Location Scale and Shape (GAMLSS) to test this hypothesis using as a case study the lobster fishery (targeting two species) in the Galapagos Marine Reserve, Ecuador. We gathered data on each of the two species of lobster on a monthly basis over seven years, including: (a) onboard observers’ records of catch data, fishing effort, and ground location by trip, and (b) data from interviews undertaken with fishers at their arrival to port, recording the same type of information as obtained from onboard observers. We use this information to analyze the effect of the measured variables and to standardize the Catch per Unit Effort (CPUE) in each case, using the GAMLSS. For both species, the temperature, region, fishing schedule, month, distance, and the monitoring system were significant variables of the selected models associated with the variability of the catch rate. ForPanulirus penicillatus, CPUE was higher at night than during the day, and forPanulirus gracilisit was higher during the day. Increased temperature resulted in a decrease of CPUE values. It was evident that temporal, spatial scales and monitoring system can influence the variability of this indicator. We contend that the identification of drivers of change of relative abundance in low-mobility species can help to support the development of monitoring and assessment programs for this type of fisheries.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
Relative Abundance ◽  
Mississippi River ◽  
Largemouth Bass ◽  
Fish Assemblage ◽  
Fish Assemblages ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Large River ◽  
Frequency Of Occurrence ◽  
Abundance And Distribution

<em>Abstract.</em>—An investigation of historical fisheries information for pools 4–13 of the upper Mississippi River (UMR) was conducted to 1) determine the pre-1938 relative abundance and distribution of bluegill <em>Lepomis macrochirus </em>and largemouth bass <em>Micropterus salmoides, </em>2) determine the composition and relative abundance of the preimpoundment fish assemblage, and 3) determine if a shift in frequency of occurrence and relative abundance has occurred due to impoundment.

Conservation, Ecology, and Management of Catfish: The Second International Symposium

2011 ◽  
Keyword(s):  
International Symposium ◽  
Size Structure ◽  
Pylodictis Olivaris ◽  
Social Event ◽  
Conservation Ecology ◽  
Party Size ◽  
Catch And Release ◽  
Flathead Catfish ◽  
Creel Survey ◽  
Total Effort

<em>Abstract</em>.—Hand grabbing for catfish has been practiced in Mississippi for many years; however, few studies have addressed this fishing technique. Ross Barnett Reservoir is a<em> Abstract</em>.—Hand grabbing for catfish has been practiced in Mississippi for many years; however, few studies have addressed this fishing technique. Ross Barnett Reservoir is a 13,360-ha impoundment located in central Mississippi that supports a substantial hand grabbing fishery. A roving creel survey was conducted during the 2007 and 2008 Mississippi hand grabbing season (May 1–July 15). Objectives were to estimate catch, harvest, and effort of hand grabbers and to solicit information concerning techniques used by these anglers. A total of 37 parties was interviewed, consisting of 150 total anglers. Seventy percent of the parties interviewed targeted flathead catfish <em>Pylodictis olivaris</em>. Ninety-five percent of the parties used a probe, and all parties fished boxes located at depths of 1–2 m. Average party size was four anglers, indicating that hand grabbing is a social event. For 2007 and 2008, anglers spent an estimated 4,424 and 5,259 h hand grabbing, respectively. An estimated 3,313 and 2,589 catfish were harvested in 2007 and 2008, respectively. Based on size structure of harvested catfish, hand grabbing anglers at Ross Barnett Reservoir do not appear to be size-selective. Most anglers were harvest-oriented, with catch-and-release estimates making up only 12% and 9%, respectively. Future creel surveys should be directed at the total effort allocated toward catfishing, in an effort to determine the effect of hand grabbing on Ross Barnett Reservoir.

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