Evaluation of Fish Communities in Daya Bay Using Biomass Size Spectrum and ABC Curve

Based on the data collected by four trawl surveys during 2016–2017, we applied biomass size spectrum (BSS) and abundance–biomass comparison (ABC) curve to assess the status of fish communities’ status in Daya Bay, China. Our findings indicated a unimodal pattern and biomass size ranged from −2 to 10 grain levels and the pattern of the Sheldon-type BSS of fish in Daya Bay. Moreover, fishes in the range of four to eight size class were relatively abundant. The highest peak belonged to the two to four grain level (log2 size bins), mainly consisting of Leiognathus brevirostris, Callionymus meridionalis, Callionymus koreanus, Evynnis cardinalis, Trachurus japonicus, and other small fishes. The curves of the BSS in spring and winter were relatively flat and comprised a large curvature. The summer and autumn curves were comparatively steep, and the seasonal curvature was small. The curvatures of the curve were mainly related to a large number of small Evynnis cardinalis and a small number of large-sized Harpadon nehereus and Leiognathus ruconius. In our study, it was observed that the number and the size of the breeding population, trophic levels, migration habits, and other life history characteristics, as well as anthropogenic disturbances (especially overfishing), significantly affected the peak shape, slope, or curvature of the fish BSS, with overfishing being the main factor. The ABC curve exhibited that Daya Bay was in a critical state of disturbance throughout the year. The spring, summer, and autumn were in severe disturbance, while the winter was in moderate disturbance.

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The status of Gould's petrel, Pterodroma leucoptera leucoptera, on Cabbage Tree Island, New South Wales

Wildlife Research ◽

10.1071/wr9950601 ◽

1995 ◽

Vol 22 (5) ◽

pp. 601 ◽

Cited By ~ 17

Author(s):

D Priddel ◽

N Carlile ◽

C Davey ◽

P Fullagar

Keyword(s):

Reproductive Output ◽

New South ◽

New South Wales ◽

Breeding Population ◽

Tree Island ◽

South Wales ◽

The Status ◽

Marginal Improvement ◽

Main Population ◽

Cabbage Tree

Gould's petrel, Pterodroma leucoptera leucoptera, breeds only on Cabbage Tree Island, New South Wales. Annual surveys to estimate the size of the breeding population and the reproductive output were conducted between 1989 and 1992. Annual estimates of the total number of pairs breeding in the two gullies containing the main population were between 122 +/- 20 (s.e.) and 202 +/- 26. Breeding success was less than 20% between 1989 and 1991, but rose to 24.7% in 1992. This marginal improvement may be the result of management action undertaken to reduce mortality of breeding adults and fledglings. The total population is estimated to have declined from 2004 (95% confidence limits: 1464,3185) in 1970 to 1479 (1250,1815) in 1992, a decline of 26% in 22 years. The reasons for this decline are unclear.

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Intensive agriculture alters the biomass size spectrum and body-mass of benthic insects: evidence from a reciprocal transfer experiment

Hydrobiologia ◽

10.1007/s10750-020-04178-1 ◽

2020 ◽

Vol 847 (5) ◽

pp. 1221-1235 ◽

Cited By ~ 1

Author(s):

Edward M. Krynak ◽

Adam G. Yates

Keyword(s):

Body Mass ◽

Intensive Agriculture ◽

Size Spectrum ◽

Transfer Experiment ◽

Benthic Insects ◽

Reciprocal Transfer ◽

Biomass Size Spectrum

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Vodne ptice in ujede Cerkniškega polja (južna Slovenija) v letih 2007 in 2008, s pregledom zanimivejših opazovanj do konca leta 2010 / Waterbirds and raptors of Cerknica polje (southern Slovenia) in 2007 and 2008, with an overview of interesting observations till the end of 2010

Acrocephalus ◽

10.2478/v10100-012-0002-z ◽

2012 ◽

Vol 33 (152-153) ◽

pp. 25-104 ◽

Cited By ~ 1

Author(s):

Dejan Bordjan

Keyword(s):

Temporal Dynamics ◽

Data Gathering ◽

Bird Species ◽

Breeding Population ◽

Research Area ◽

Phalacrocorax Carbo ◽

Waterbird Species ◽

Fulica Atra ◽

The Status ◽

Conservation Concern

Between the end of February 2007 and mid-February in 2008, 73 systematic surveys of waterbirds and raptors were carried out during 10-day periods at Cerknica polje (Southern Slovenia). The main objectives of our research were: to ascertain the abundance and temporal dynamics of the species occurring here, to specify their status, to make a comparison with the past period of systematic data gathering in the 1991-1992 period, to present estimates of the breeding, migrating and wintering populations, as well as to make, on these bases, a nature-conservancy evaluation of the area. Other ornithological data, acquired till the end of 2010, were gathered as well. Between the beginning of May and the beginning of September 2007, the water in the area virtually ran dry (it was retained only in the channels of the streams), while the surface itself was partially or fully icebound from mid-November 2007 till the beginning of February 2008. By the end of 2010, a total of 129 waterbird and raptor species were recorded at Cerknica polje, while in the 2007-2008 period 83 were registered. Dynamics of the species occurrence with more than nine observations made in the area is presented in a greater detail in the species overview. The breeding status was held by 27 bird species, while further seven were forage guests that bred in the vicinity of the study area. Most of the species (118) had the status of passage visitor, whereas those with the status of summer visitor (34) and winter visitor (40) were fewer. Among the recorded species, 34 were accidental and 21 rare visitors. There were 16 winter and seven summer residents, while year-round residents were six. In all 10-day periods of the research period, four species were recorded: Mallard Anas plathyrhynchos, Grey Heron Ardea cinerea, Buzzard Buteo buteo and Kestrel Falco tinnunculus. In more than 90% of 10-day periods, the Great Egret Ardea alba was recorded as well. In the 2007-2008 period, two species were eudominant (Mallard 27.2%, Buzzard 10.1%), whereas another two were dominant (Garganey Anas querquedula 7.4%, Coot Fulica atra 6.4%). Most individuals were registered at the end of March and in early April (up to 1,978 ind.), whereas the greatest numbers of species (48) were recorded in mid-April. Between May and August, the numbers of individuals and species were low owing to the dried up lake. The smallest area of occurrence was occupied by the Cormorant Phalacrocorax carbo and a group of ducks of the genera Aythya, Bucephala and Mergellus. Gulls, egrets, herons, waders, harriers Circus sp. and the Red-footed Kestrel Falco vespertinus occurred in the greater part of the research area. 10 breeders fulfilled the criteria of the species of the greatest conservation importance, two of which (Ferruginous Duck Aythya nyroca and Curlew Numenius arquata) are species of global conservation concern, whereas seven are of conservation concern on a European scale. Among non-breeders, 14 waterbird species and raptors occurred in significant numbers (> 0.1% biogeographical population), five of which occurred at least occasionally with more than 1% of their biographical population. Two species (Red-necked Grebe Podiceps grisegena and Snipe Gallinago gallinago) breed in Slovenia only at Cerknica polje, while further six species have here at least 40% of their Slovenian breeding population

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Comparison and utility of different size-based metrics of fish communities for detecting fishery impacts

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f05-261 ◽

2006 ◽

Vol 63 (4) ◽

pp. 810-820 ◽

Cited By ~ 11

Author(s):

Daniel E Duplisea ◽

Martin Castonguay

Keyword(s):

Standing Stock ◽

Fish Communities ◽

Ecosystem Approach ◽

Size Spectrum ◽

Size Spectra ◽

Predator Prey ◽

Similar Information ◽

Chance Events ◽

Length Frequency Analysis ◽

Scientific Survey

The use of fish community indicators based on size spectra has become popular in the development of an ecosystem approach to fisheries. Size spectrum theory arose from basic ecological work on energy flow, predatorprey interactions, and biomass standing stock and was later applied to fish communities as lengthfrequency analysis. A multitude of size spectrum indicators have resulted, but it is not clear if they all present similar information. Here we develop a simple framework describing what four size spectra indicators suggest about fish communities, their likely response to fisheries exploitation, their ecological interpretation, and some of their biases. We examined indicators for scientific survey data from six exploited North Atlantic fish communities for the information that they reveal about each community. Each indicator revealed different information and had different biases. Combining indicators for the most impacted system (owing to fisheries and environmental change), the eastern Scotian Shelf, revealed a pattern analogous to Holling's ecological cycle of exploitation, conservation, release, and reorganisation. If this analogy is generally valid, then it suggests that collapsed fish communities are more susceptible to chance events, and recovery is not directly reversible and may not be recoverable (to previous known state) at all if the system moves to an alternative cycle.

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Does a recent surge in Socotra Cormorant Phalacrocorax nigrogularis nesting population and establishment of new breeding colonies ensure long term conservation? Pragmatic assessment of recent augmentation in Abu Dhabi Emirate, UAE

Bird Conservation International ◽

10.1017/s0959270918000242 ◽

2018 ◽

Vol 29 (03) ◽

pp. 361-369

Author(s):

SHAHID B. KHAN ◽

SÁLIM JAVED ◽

SHAKEEL AHMED ◽

EISSA ALI AL HAMMADI ◽

ABDULLAH ALI AL HAMMADI ◽

...

Keyword(s):

United Arab Emirates ◽

Public Awareness ◽

Fold Increase ◽

Breeding Population ◽

Abu Dhabi ◽

Breeding Sites ◽

The Status ◽

Abu Dhabi Emirate ◽

Pragmatic Assessment

SummaryUnited Arab Emirates is an important range country for the ‘Vulnerable’ Socotra Cormorant Phalacrocorax nigrogularis and Abu Dhabi Emirate holds most of the remaining breeding colonies. Emirate-wide monitoring of all breeding colonies was undertaken annually for 11 breeding seasons from 2006–2007 to 2016–2017 to monitor the status of breeding colonies and estimate the nesting population. Breeding was recorded in 10 colonies that were used intermittently with an average of four (± 1.3 SD) colonies active each year. The highest number of eight active colonies was recorded in 2016–2017. Establishment of two new breeding colonies on Butinah and Digala in 2016–2017 and recolonisation of three previously inactive colonies during the monitoring period emphasised the ability of the species to relocate and colonise suitable sites. Continued threats at some breeding colonies caused abandonment and subsequent relocation, resulting in a gradual shift of breeding colonies to safer areas. Presently, most of the breeding sites (62%) with an increased number of breeding birds are found in colonies with restricted access. The Emirate-wide nesting population witnessed a 10-fold increase in the last decade; after an initial decline in 2006–2007 it increased from about 5,000 pairs in 2007–2008 to nearly 52,000 nesting pairs in 2016–2017. Combined with the nesting population from the Siniya colony, the overall UAE nesting population is estimated at 60,000 to 70,000 pairs, nearly half of the global breeding population. Further augmentation of the current breeding numbers is possible if breeding colonies remain safe from human disturbance and invasive predators. For long-term conservation of Socotra Cormorant, protection of all remaining colony sites, including inactive ones, is important in addition to minimising disturbance along with widespread public awareness to change the people’s perception of the species as a competitor to commercial fisheries.

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A Standardized Workflow Based on the STAVIRO Unbaited Underwater Video System for Monitoring Fish and Habitat Essential Biodiversity Variables in Coastal Areas

Frontiers in Marine Science ◽

10.3389/fmars.2021.689280 ◽

2021 ◽

Vol 8 ◽

Author(s):

Dominique Pelletier ◽

David Roos ◽

Marc Bouchoucha ◽

Thomas Schohn ◽

William Roman ◽

...

Keyword(s):

Spatial Scales ◽

Conservation Status ◽

Fish Communities ◽

Coastal Areas ◽

Trophic Levels ◽

Underwater Video ◽

Benthic Habitats ◽

Management Actions ◽

Essential Biodiversity Variables ◽

Cost Efficient

Essential Biodiversity Variables (EBV) related to benthic habitats and high trophic levels such as fish communities must be measured at fine scale but monitored and assessed at spatial scales that are relevant for policy and management actions. Local scales are important for assessing anthropogenic impacts, and conservation-related and fisheries management actions, while reporting on the conservation status of biodiversity to formulate national and international policies requires much broader scales. Measurements must account for the fact that coastal habitats and fish communities are heterogeneously distributed locally and at larger scales. Assessments based on in situ monitoring generally suffer from poor spatial replication and limited geographical coverage, which is challenging for area-wide assessments. Requirements for appropriate monitoring comprise cost-efficient and standardized observation protocols and data formats, spatially scalable and versatile data workflows, data that comply with the FAIR (Findable, Accessible, Interoperable, and Reusable) principles, while minimizing the environmental impact of measurements. This paper describes a standardized workflow based on remote underwater video that aims to assess fishes (at species and community levels) and habitat-related EBVs in coastal areas. This panoramic unbaited video technique was developed in 2007 to survey both fishes and benthic habitats in a cost-efficient manner, and with minimal effect on biodiversity. It can be deployed in areas where low underwater visibility is not a permanent or major limitation. The technique was consolidated and standardized and has been successfully used in varied settings over the last 12 years. We operationalized the EBV workflow by documenting the field protocol, survey design, image post-processing, EBV production and data curation. Applications of the workflow are illustrated here based on some 4,500 observations (fishes and benthic habitats) in the Pacific, Indian and Atlantic Oceans, and Mediterranean Sea. The STAVIRO’s proven track-record of utility and cost-effectiveness indicates that it should be considered by other researchers for future applications.

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Study on Presentation System for Walking Training Using High-Performance Shoes

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2015.p0706 ◽

2015 ◽

Vol 27 (6) ◽

pp. 706-713 ◽

Cited By ~ 1

Author(s):

Yasuhiro Hayakawa ◽

◽

Shogo Kawanaka ◽

Kazuma Kanezaki ◽

Kosei Minami ◽

...

Keyword(s):

Pressure Distribution ◽

Physical Performance ◽

Accidental Falls ◽

High Performance ◽

Distribution Patterns ◽

The Elderly ◽

Training System ◽

The Body ◽

The Status ◽

Main Factor

<div class=""abs_img""><img src=""[disp_template_path]/JRM/abst-image/00270006/13.jpg"" width=""300"" /> Proposed walking training system</div>The number of accidental falls has been increasing among the elderly as society has aged. The main factor is a deteriorating center of balance due to declining physical performance. Another major factor is that the elderly tend to have bowlegged walking and their center of gravity position of the body tend to swing from side to side during walking. To find ways to counteract falls among the elderly, we developed walking training system to treat the gap in the center of balance. We also designed High-Performance Shoes that showed the status of a person’s balance while walking. We also produced walk assistance from the insole in which insole stiffness corresponding to human sole distribution could be changed to correct the person’s walking status. We constructed our High-Performances Shoes to detect pressure distribution during walking. Comparing normal sole distribution patterns and corrected ones, we confirmed that our assistance system helped change the user’s posture, thereby reducing falls among the elderly.

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Cormorant predation overlaps with fish communities and commercial-fishery interest in a Swedish lake

Marine and Freshwater Research ◽

10.1071/mf16227 ◽

2017 ◽

Vol 68 (9) ◽

pp. 1677 ◽

Cited By ~ 3

Author(s):

M. K. Ovegård ◽

K. Öhman ◽

J. S. Mikkelsen ◽

N. Jepsen

Keyword(s):

Water Quality ◽

Fish Communities ◽

Common Species ◽

Predatory Fish ◽

Commercial Fishery ◽

Phalacrocorax Carbo ◽

Phalacrocorax Carbo Sinensis ◽

Gill Net ◽

Pike Perch ◽

Main Factor

The increase of the fish-eating cormorant (Phalacrocorax carbo sinensis) in Europe has resulted in conflicts with fisheries. In Lake Roxen, Sweden, cormorants are blamed for causing a decrease in fishery catches. To study and describe the potential effects that cormorants may have had on fish in the lake, their diet was analysed in relation to fish catches in gill-net surveys and fishery catches. Estimates of predation were achieved by ‘tag and recovery’ on eel, pike-perch and perch. Cormorants predated on the most common species and sizes, which were mainly smaller perch, ruffe and roach (mean sizes of 9, 8 and 13cm respectively). Tag recoveries from perch, eel and pike-perch detected predation estimates of 14, 7 and 15% respectively. From a highly eutrophic state, the lake has shown improvements in water quality and a development towards larger predatory fish was expected, but the results from gill-net surveys did not show this. Results indicated that cormorants and fisheries may both be responsible, but because cormorants remove more fish, they may be the main factor for the lack of recovery of large predatory fish. Their predation keeps recruitment high, but the number of fish that reach large sizes remains low.

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Biodiversity–ecosystem functioning relationships in fish communities: biomass is related to evenness and the environment, not to species richness

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.1189 ◽

2019 ◽

Vol 286 (1906) ◽

pp. 20191189 ◽

Cited By ~ 5

Author(s):

Aurore Maureaud ◽

Dorothee Hodapp ◽

P. Daniël van Denderen ◽

Helmut Hillebrand ◽

Henrik Gislason ◽

...

Keyword(s):

Species Richness ◽

Ecosystem Functioning ◽

Structural Equation ◽

Fish Assemblages ◽

Current Knowledge ◽

Marine Ecosystem ◽

Experimental Studies ◽

Fish Communities ◽

Trophic Levels ◽

Fish Biomass

The relationship between biodiversity and ecosystem functioning (BEF) is a topic of considerable interest to scientists and managers because a better understanding of its underlying mechanisms may help us mitigate the consequences of biodiversity loss on ecosystems. Our current knowledge of BEF relies heavily on theoretical and experimental studies, typically conducted on a narrow range of spatio-temporal scales, environmental conditions, and trophic levels. Hence, whether a relationship holds in the natural environment is poorly understood, especially in exploited marine ecosystems. Using large-scale observations of marine fish communities, we applied a structural equation modelling framework to investigate the existence and significance of BEF relationships across northwestern European seas. We find that ecosystem functioning, here represented by spatial patterns in total fish biomass, is unrelated to species richness—the most commonly used diversity metric in BEF studies. Instead, community evenness, differences in species composition, and abiotic variables are significant drivers. In particular, we find that high fish biomass is associated with fish assemblages dominated by a few generalist species of a high trophic level, who are able to exploit both the benthic and pelagic energy pathway. Our study provides a better understanding of the mechanisms behind marine ecosystem functioning and allows for the integration of biodiversity into management considerations.

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