The bluefish Pomatomus saltatrix (Pisces: Pomatomidae) in the Adriatic and Tyrrhenian Seas, can we call it climate invader?

Mapping Intimacies ◽

10.31230/osf.io/h8t35 ◽

2020 ◽

Author(s):

Jacopo Cerri ◽

Ernesto Azzurro

Keyword(s):

Invasive Species ◽

Climate Warming ◽

Temporal Dynamics ◽

Small Scale ◽

Ecological Knowledge ◽

Pomatomus Saltatrix ◽

Warm Water Species ◽

Northward Expansion ◽

Spatio Temporal ◽

Water Species

Here, we investigate the recent spatio-temporal dynamics of the bluefish Pomatomus saltatrix, a warm water species, which is considered to have conquered the northern Mediterranean coasts due to climate warming. Capitalizing two independent surveys carried out through online questionnaires and vis-à-vis interviews, we accessed the ecological knowledge of 640 recreational fishers, and 206 small-scale fishers, respectively. Respondents provided coherent evidence of a rapid northward expansion of the bluefish along the Tyrrhenian and Adriatic Seas at an estimated speed of 0.8-1.4 degrees of latitude per year. Most fishers in the two seas believed the bluefish to negatively affect both fishing activities and the environment, just as if it was an invasive species and this negative perception was positively correlated with increasing bluefish abundances. The phenomenological effects of this widespread outbreak can be assimilated to a large invasion across various sectors of the Mediterranean Sea, posing the urgency of manage this issue and better understanding its linkage to climate drivers.

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The shifting distribution of Mediterranean fishes: a spatio-temporal assessment based on Local Ecological Knowledge .

10.31230/osf.io/zgupd ◽

2019 ◽

Cited By ~ 2

Author(s):

Ernesto Azzurro ◽

Valerio Sbragaglia ◽

Jacopo Cerri ◽

Michel Bariche ◽

Luca Bolognini ◽

...

Keyword(s):

Mediterranean Sea ◽

Temporal Dynamics ◽

Local Ecological Knowledge ◽

Rapid Change ◽

Species Abundance ◽

Global Ocean ◽

Small Scale ◽

Ecological Knowledge ◽

The Mediterranean ◽

Spatio Temporal

A major problem worldwide is the rapid change in species abundance and distribution, which is rapidly restructuring the biological communities of many ecosystems under changing climates. Tracking these transformations in the marine environment is crucial but our understanding is often hampered by the absence of historical data and by the practical challenge of survey large geographical areas. Here we focus on the Mediterranean Sea, a region which is warming faster than the rest of the global ocean, tracing back the spatio-temporal dynamic of species, which are emerging the most in terms of increasing abundances and expanding distributions. To this aim, we accessed the Local Ecological Knowledge (LEK) of small-scale and recreational fishers reconstructing the dynamics of fish perceived as ‘new’ or increasing in different fishing area. Over 500 fishers across 95 locations and 9 different countries were interviewed and semi-quantitative information on yearly changes in species abundance was collected. Overall, 75 species were mentioned by the respondents, being the most frequent citations related to warm-adapted species of both, native and exotic origin. Respondents belonging to the same biogeographic sectors described coherent spatio-temporal dynamics, and gradients along latitudinal and longitudinal axes were revealed. This information provides a more complete understanding of recent bio-geographical changes in the Mediterranean Sea and it also demonstrates that adequately structured LEK methodology might be applied successfully beyond the local scale, across national borders and jurisdictions. Acknowledging this potential through macro-regional coordination, could pave the ground for future large-scale aggregations of individual observations, increasing our potential for integrated monitoring and conservation planning at the regional or even global level.

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Studying the Spatio-Temporal Dynamics of Small-Scale Events in Twitter

Proceedings of the 29th on Hypertext and Social Media - HT '18 ◽

10.1145/3209542.3209561 ◽

2018 ◽

Cited By ~ 1

Author(s):

Paul Mousset ◽

Yoann Pitarch ◽

Lynda Tamine

Keyword(s):

Temporal Dynamics ◽

Small Scale ◽

Spatio Temporal

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Large scale northward expansion of warm water species Skeletonema tropicum (Bacillariophyceae) in China seas

Chinese Journal of Oceanology and Limnology ◽

10.1007/s00343-012-1249-x ◽

2012 ◽

Vol 30 (4) ◽

pp. 519-527 ◽

Cited By ~ 4

Author(s):

Dongyan Liu ◽

Jinjie Jiang ◽

Yan Wang ◽

Yong Zhang ◽

Baoping Di

Keyword(s):

Large Scale ◽

Warm Water ◽

China Seas ◽

Warm Water Species ◽

Northward Expansion ◽

Water Species

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Structure and spatio-temporal dynamics of the artisanal small-scale fisheries at the future MPA of “Taza” (Algerian coast, SW Mediterranean)

Mediterranean Marine Science ◽

10.12681/mms.16192 ◽

2018 ◽

Vol 19 (3) ◽

pp. 555 ◽

Cited By ~ 2

Author(s):

IBRAHIM BOUBEKRI ◽

ALEX JAMES CAVEEN ◽

ABDALLAH BORHANE DJEBAR ◽

RACHID AMARA ◽

HUBERT MAZUREK

Keyword(s):

Temporal Dynamics ◽

Field Work ◽

Management Plan ◽

Small Scale ◽

Target Species ◽

Small Scale Fisheries ◽

The Future ◽

Mullus Surmuletus ◽

Spatio Temporal ◽

Management Approaches

Artisanal Small-Scale Fisheries (SSFs) are a primordial and very diverse activity in the Mediterranean, also within Marine Protected Areas (MPAs). This diversity is explained in terms of target species, gears, and fishing strategies. The main objective of this work was to investigate the spatio-temporal dynamics of artisanal SSFs of the future MPA of “Taza” (Algeria, SW Mediterranean). Data were collected through direct assessment of daily landings and using questionnaires. They were the subject of multivariate analyses that allowed us to identify the métiers practiced by artisanal fishers. During the one year (May 2013 to April 2014) field work period, 1330 fishing trips and 1613 fishing operations in 16 fishing grounds were recorded in the Ziama fishing harbor, where 15.2 tons of total catch was assessed. Our results show that, in the study area, the boats are predominantly gillnetters and that among the five métiers characterized by target species, gear type, fishing grounds, and fishing seasons, two métiers (“Mullus surmuletus trammel net” and “Sparids monofilament gillnet”) are practiced throughout the year, while the remaining three (“Sarda sarda driftnet”, “Merluccius merluccius set gillnet”, and “Pagellus set gillnet”) are specific to a determined period of the year. The ‘Mullus surmuletus trammel net’ métier represents 40% of the total fishing operations, of which 57.5% are carried out in the coastal sector at - 25 m. This study could contribute to defining the appropriate management approaches for SSFs in the future MPA of “Taza” by providing baseline information to build a sound management plan. In Algeria, it will certainly serve as a scientific reference in terms of zoning, protection of biodiversity, and specific monitoring at particular locations and periods of the year for the sustainable management of MPAs.

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Small-scale spatio-temporal variability in ichthyoplankton and zooplankton distribution in relation to a tidal-mixing front in the Irish Sea

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2005.04.016 ◽

2005 ◽

Vol 62 (6) ◽

pp. 1021-1036 ◽

Cited By ~ 26

Author(s):

O. Lee ◽

R.D.M. Nash ◽

B.S. Danilowicz

Keyword(s):

Temporal Dynamics ◽

Fish Larvae ◽

Sampling Period ◽

Tidal Mixing ◽

Irish Sea ◽

Small Scale ◽

Surface Salinity ◽

Average Value ◽

Tidal Mixing Front ◽

Spatio Temporal

Abstract This study examines the spatio-temporal dynamics of fish larvae and their prey at a tidal-mixing front in the central Irish Sea. The distribution of ichthyoplankton and zooplankton was analysed in relation to environmental variables (depth, surface temperature, surface salinity, and water column stratification) using Redundancy Analysis (RDA). Significant interannual variability in the formation and position of the tidal-mixing front coincided with large differences in the species abundances of both ichthyoplankton and zooplankton. During the summer, ichthyoplankton and zooplankton communities were structured by a combination of depth and hydrography, and the variability in species composition was directly related to the average value of the stratification parameter. Several ichthyoplankton species were consistently associated with frontal waters, while fewer species were concentrated in mixed water masses throughout the sampling period. The distribution of individual zooplankton species was also examined, and water mass affinities were shown to vary with developmental stage.

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Object-Based Flood Analysis Using a Graph-Based Representation

10.5194/egusphere-egu2020-4922 ◽

2020 ◽

Author(s):

Bos Debusscher ◽

Frieke Van Coillie

Keyword(s):

Temporal Dynamics ◽

Ground Truth ◽

Small Region ◽

Water Area ◽

Small Scale ◽

Mapping Unit ◽

Object Based ◽

Flood Analysis ◽

Spatio Temporal ◽

Sar Imagery

Describing spatio-temporal dynamics of a flood using an object-based approach with a graph-based representation proved useful for analysis of small-scale flood dynamics in Belgium (about 100 km&#178;) (Debusscher, et al., 2019). &#160;Starting from pre-processed Sentinel-1 SAR imagery, the water bodies are delineated in each timestep (using a thresholding algorithm), after which all water-polygons are grouped into graphs according to their spatial overlap on consecutive timesteps. &#160;Change in (water)area and backscatter are used to quantify the amount of variation. &#160;Products of this tool are a global variation map covering the whole study are, and a temporal profile for each waterbody, visually describing the evolution of the backscatter and number of polygons that make up the waterbody. &#160; After establishing this proof of concept in a small region (flood of June 2016 in Schulensbroek, a nature reserve in north-eastern Belgium), this approach is applied on floods covering larger areas (about 10000 km&#178;). &#160;Two cases are studied, the Mozambique flood of March 2019 (near Beira) and the India flood of September 2019 (near Patna). &#160;The process of upscaling leads to solving issues regarding the minimal mapping unit, adding extra pre-processing in order to simplify polygons (morphological operators), increasing code efficiency (mainly regarding for-loops). In the absence of ground truth, produced flood maps are compared to existing flood extent maps (from Disaster Charter (unitary) and Hasard (LIST)) in order to estimate accuracy.References Debusscher Bos and Van Coillie Frieke Object-Based Flood Analysis Using a Graph-Based Representation, Remote Sensing. - 2019. - p. p. 1883.&#160;

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