Home range of European lobster (Homarus gammarus) in a marine reserve: implications for future reserve design

2011 ◽  
Vol 68 (7) ◽  
pp. 1197-1210 ◽  
Author(s):  
Even Moland ◽  
Esben Moland Olsen ◽  
Kristian Andvord ◽  
Jan Atle Knutsen ◽  
Nils Chr. Stenseth

Marine reserves are perceived as a critical component in successful rebuilding of overharvested marine populations. Such efforts can be particularly successful in species with limited movement rates. However, long-term data on movement is sparse for most marine species. Here, we investigated space use in European lobster ( Homarus gammarus ) by ultrasonic tracking in a reserve on the Norwegian Skagerrak coast from September 2006 to August 2007. Over the period, 95% of tagged lobsters remained either within the reserve or near reserve boundaries. Home range estimates based on a kernel density estimator of the 95% utilization distribution ranged from 5728 to 41 548 m2 (mean 19 879 ± 2152 m2 standard error), representing 0.57%–4.15% of the reserve area (1 km2), with no significant difference among males, non-ovigerous females, and ovigerous females for an overlapping observation period of 242 days. Logistic regression predicted average time to reach 50% and 95% of minimum convex polygon home range area at 98 and 259 days, respectively. These results show that European lobsters can be resident with limited home ranges. Small coastal reserves can be designed to afford complete or partial protection by letting boundaries engulf or intersect patches of habitat preferred by this species.

2004 ◽  
Vol 31 (3) ◽  
pp. 327 ◽  
Author(s):  
Helen Puckey ◽  
Milton Lewis ◽  
David Hooper ◽  
Carrie Michell

Radio-telemetry was used to examine the home range, movement and habitat utilisation of the critically endangered Carpentarian rock-rat (Zyzomys palatalis) in an isolated habitat patch in the Gulf of Carpentaria hinterland over a 13-month period. Two home-range estimators were used in the study, (i) minimum convex polygon (MCP) and (ii) fixed Kernel (KL), the latter also being used to estimate core areas of activity. Based on a total sample size of 21 individuals, the mean MCP home range was 11 165 m2, similar to the mean KL home range of 10 687 m2. Core areas were, on average, 11.9% of the KL home-range estimate. There was no significant difference in the size of home range or core area of males and females. Juveniles had a significantly smaller home range than adults. Home ranges and, to a lesser degree, core areas were non-exclusive, with multiple areas of overlap (averaging 41% and 38% respectively) within and between all age and gender categories, but especially between males and between juveniles. Movement frequencies showed that animals made many short forays in a central area close to the arithmetic home-range mean and far fewer long forays of distances greater than 100 m from the central area. The spatial and temporal activity of Z. palatalis was concentrated in, but not confined to, the 'valley' and 'slope' habitats, with fewer movements of rats onto the surrounding 'plateau'. Resource selection analyses showed that Z. palatalis tended to prefer valley and slope habitats over the plateau and that the proportion of point locations was significantly higher for adults in the slope habitat and for juveniles in the valley habitat. Most home ranges were centred on the ecotone between these two habitat types. Although isolated and spatially limited, these habitat patches provide high-quality resources for dense populations of Z. palatalis. This study exemplifies a species' attempt to make efficient use of a limited resource in an otherwise hostile environment. Even small declines in habitat area or quality due to their vulnerability to fire would impact upon many animals.


The Auk ◽  
2019 ◽  
Vol 136 (2) ◽  
Author(s):  
Csaba Moskát ◽  
Miklós Bán ◽  
Attila Fülöp ◽  
Judit Bereczki ◽  
Márk E Hauber

Abstract Obligate brood parasitic birds have evolved a rare avian strategy for reproduction by laying eggs in the nests of other species. In doing so, their breeding ranges, but not necessarily their foraging habitats, have become intimately related to the nesting territories of their hosts. We studied home range sizes and distribution patterns in Common Cuckoos (Cuculus canorus) on their breeding grounds in central Hungary, where cuckoos parasitize only Great Reed Warblers (Acrocephalus arundinaceus) in channel-side reed-beds at a high frequency (>50%). The geographic coordinates of tagged cuckoos were monitored by high-precision, remotely downloadable non-Platform Terminal Transmitter global positioning system (GPS) loggers, attached to 9 females and 6 males. Our results revealed bimodal use of habitat patches: (1) the home ranges of male and female cuckoos were packed densely along the channels where the hosts breed, and their distribution maps had high overlaps between sexes; (2) ~71% of cuckoos also visited nearby woodland patches, presumably for foraging, where the host species was not present. The size of cuckoo home ranges varied to an unusually great extent: 0.3–185 km2 as calculated by the minimum convex polygon method (85%), or 1–17 km2 when calculated by the more suitable kernel density estimation (KDE) method (Utilization Distribution 85%) for patchy habitats. Male and female cuckoos had similar home range sizes as estimated by the KDE method, consisting of 1–4 areas within the 2 habitat types of channel reed-beds and woodlands. No preference was revealed for night roosting locations between the 2 habitats or sexes. Female cuckoos were more likely to use reed-beds in the afternoons, when females parasitize host nests. Remote downloadable GPS methods offer an effective way of tracking cuckoos across large areas, but the estimation of home range sizes requires caution due to this species’ patchy and disconnected habitat use.


1993 ◽  
Vol 20 (5) ◽  
pp. 571 ◽  
Author(s):  
S Troy ◽  
G Coulson

Home range in the swamp wallaby, Wallabia bicolor (Marsupialia : Macropodoidea) was examined using radio-tracking in a 150-ha remnant of mixed eucalypt forest at Healesville, Victoria. Three methods were used to calculate home-range size: minimum convex polygons, fourier transform MAP(O.95) and MAP(0.50) estimation, and harmonic mean 50% isopleths and 95% isopleths. The minimum convex polygon method produced the largest estimate of home-range area (16.01 +/-.45 ha). Each method required a different number of fixes before home-range area estimates reached an asymptote. These data showed that W. bicolor have small, overlapping home ranges and that the shape of the home range varied between individuals. Home-range area was larger than previously reported for this species, and there was no significant difference between the sexes in home-range size.


2009 ◽  
Vol 123 (2) ◽  
pp. 126 ◽  
Author(s):  
Richard D. Weir ◽  
Alton S. Harestad ◽  
Fraser B. Corbould

We described the size and spatial arrangement of aggregate and seasonal home ranges for 17 radio-tagged resident Fishers (Martes pennanti) that were >1.5 years old in two areas of central British Columbia during 1990-1993 and 1996-2000. We estimated home range size for each Fisher from the 95% isopleth of the utilization distribution generated using a fixed kernel model with smoothing selected by least-squares cross-validation (95% FK). For comparison to previous studies, we also calculated the minimum convex polygon estimate of home range size (MCP) for each animal. The aggregate home ranges (95% FK) of female Fishers (mean = 37.9 km², SD = 18.5, range = 10.5 – 81.2, n = 11) were significantly smaller than those of males (mean = 161.3 km², SD = 100.0, range = 46.0 – 225.2, n = 3; P = 0.019). We observed minor overlap among 95% FK home ranges of Fishers of the same sex, but considerable overlap among home ranges of males and females. Home ranges (95% FK or MCP) that we observed in central British Columbia were larger than those reported elsewhere in North America, particularly for males. We suggest that the distribution of resources for Fishers may occur at lower gross densitiesin central British Columbia than in other portions of the Fisher’s range and that suitable habitat in which Fishers can establish home ranges is not found uniformly across the landscape.


2016 ◽  
Vol 64 (4) ◽  
Author(s):  
Jaime Andres Cabrera ◽  
Eduardo Molina ◽  
Tania Gonzalez ◽  
Dolors Armenteras

Telemetry based on Global Positioning Systems (GPS) makes possible to gather large quantities of information in a very fine scale and work with species that were impossible to study in the past. When working with GPS telemetry, the option of storing data on board could be more desirable than the sole satellite transmitted data, due to the increase in the amount of locations available for analysis. Nonetheless, the uncertainty in the retrieving of the collar unit makes satellite-transmitted technologies something to take into account. Therefore, differences between store-on-board (SoB) and satellite-transmitted (IT) data sets need to be considered. Differences between SoB and IT data collected from two lowland tapirs (Tapirus terrestris), were explored by means of the calculation of home range areas by three different methods: the Minimum Convex Polygon (MCP), the Fixed Kernel Density Estimator (KDE) and the Brownian Bridges (BB). SoB and IT data sets were similar, with fix ranging from 63% to 85% respectively and 16 m to 17 m horizontal errors. Depending on the total number of locations available for each individual, the home ranges estimated showed differences between 2.7% and 79.3%, for the 50% probability contour and between 9.9% and 61.8% for the 95% probability contour. These differences imply variations in the spatial coincidence of the estimated home ranges. We conclude that the use of IT data is not a good option for the estimation of home range areas if the collar settings have not been designed specifically for this use. Nonetheless, geographical representations of the IT based estimators could be of great help to identify areas of use, besides its assistance to locate the collar for its retrieval at the end of the field season and as a proximate backup when collars disappear.


2006 ◽  
Vol 28 (1) ◽  
pp. 39 ◽  
Author(s):  
P. D. Meek ◽  
S. L. Radford ◽  
B. L. Tolhurst

Individuals from a population of Hastings River mouse (Pseudomys oralis) were radio tracked in a short-term investigation of home range, habitat use and movement patterns in Marengo State Forest on the northern tablelands of New South Wales. Results were assessed in the context of conservation and management of this threatened species and compared to research in other parts of the species? distribution. The mean summer-autumn home range (Minimum Convex Polygon) of five animals that met the home range asymptote was 0.78�ha, the minimum home range for fourteen mice was 0.72�ha, while median home range for males was 0.8�ha and females 0.53�ha. There was no significant difference in home range size between sexes. Habitat data indicated that fallen logs, including tree head and butt residue following logging, are important refuge and nest sites, even when rocks and hollows are available. A diversity of fern and other ground plant species (including grasses) was important habitat for the species, microhabitat consisting predominantly of sedge and rush was not favoured.


2019 ◽  
Vol 76 (6) ◽  
pp. 1871-1881 ◽  
Author(s):  
Matthew T Coleman ◽  
Joanne S Porter ◽  
Michael C Bell

Abstract This article examines two important components of measurement of fecundity in the European lobster Homarus gammarus: (i) comparing the traditional gravimetric dry weight fecundity method against two non-invasive depth gauge methods initially developed for Homarus americanus and (ii) utilizing the depth gauge method to determine egg loss during the brooding period and its impacts on effective fecundity estimates. No significant difference was observed between fecundity estimates derived using either the traditional or depth gauge methods. Derived fecundity estimates from the two depth gauge methods differed by −0.31% (±2.7 s.e.) for cylinder and −1.1% (±2.4 s.e.) for ellipsoid fecundity estimates compared with the traditional method. This highlights the utility of the depth gauge method for providing fast, reliable and low-cost estimates without sacrificing lobsters or their egg masses. Egg loss is estimated to be as high as 44% from initial extrusion to hatching. The application of the non-invasive methods for estimating fecundity to other fisheries and stocks is discussed along with the importance of understanding egg loss in this commercially valuable fishery.


2011 ◽  
Vol 429 ◽  
pp. 197-207 ◽  
Author(s):  
E Moland ◽  
E Moland Olsen ◽  
H Knutsen ◽  
JA Knutsen ◽  
SE Enersen ◽  
...  

2021 ◽  
Vol 26 (2) ◽  
pp. 36
Author(s):  
Alejandro Estrada-Padilla ◽  
Daniela Lopez-Garcia ◽  
Claudia Gómez-Santillán ◽  
Héctor Joaquín Fraire-Huacuja ◽  
Laura Cruz-Reyes ◽  
...  

A common issue in the Multi-Objective Portfolio Optimization Problem (MOPOP) is the presence of uncertainty that affects individual decisions, e.g., variations on resources or benefits of projects. Fuzzy numbers are successful in dealing with imprecise numerical quantities, and they found numerous applications in optimization. However, so far, they have not been used to tackle uncertainty in MOPOP. Hence, this work proposes to tackle MOPOP’s uncertainty with a new optimization model based on fuzzy trapezoidal parameters. Additionally, it proposes three novel steady-state algorithms as the model’s solution process. One approach integrates the Fuzzy Adaptive Multi-objective Evolutionary (FAME) methodology; the other two apply the Non-Dominated Genetic Algorithm (NSGA-II) methodology. One steady-state algorithm uses the Spatial Spread Deviation as a density estimator to improve the Pareto fronts’ distribution. This research work’s final contribution is developing a new defuzzification mapping that allows measuring algorithms’ performance using widely known metrics. The results show a significant difference in performance favoring the proposed steady-state algorithm based on the FAME methodology.


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