Nest usurpation: a specialised hunting strategy used to overcome dangerous spider prey

Abstract The fishing cat’s persistence in a ‘semi-aquatic niche’ suggests the evolution of a successful hunting strategy. We describe it for the first time by analysing 197 camera-trap video-clips, collected from a participatory-science initiative, within an ethogram framework. The cats spent ∼52% of the time sitting and waiting for prey (fishes) to come nearer and took limited attempts to hunt (3.89%) in deeper waters (in which the upper portions of the cat’s body were submerged), where its hunting success was found to be 42.86%. In shallow waters, it adopted a predominantly active mode of hunting (∼96%) to flush out prey.

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Nature-Inspired Whale Optimization Algorithm for Optimal Coordination of Directional Overcurrent Relays in Power Systems

Energies ◽

10.3390/en12122297 ◽

2019 ◽

Vol 12 (12) ◽

pp. 2297 ◽

Cited By ~ 7

Author(s):

Wadood ◽

Khurshaid ◽

Farkoush ◽

Yu ◽

Kim ◽

...

Keyword(s):

Power Systems ◽

Optimization Algorithm ◽

Operating Time ◽

Whale Optimization Algorithm ◽

Humpback Whales ◽

Test Systems ◽

Whale Optimization ◽

Overcurrent Relays ◽

Optimal Coordination ◽

Hunting Strategy

In power systems protection, the optimal coordination of directional overcurrent relays (DOCRs) is of paramount importance. The coordination of DOCRs in a multi-loop power system is formulated as an optimization problem. The main objective of this paper is to develop the whale optimization algorithm (WOA) for the optimal coordination of DOCRs and minimize the sum of the operating times of all primary relays. The WOA is inspired by the bubble-net hunting strategy of humpback whales which leads toward global minima. The proposed algorithm has been applied to six IEEE test systems including the IEEE three-bus, eight-bus, nine-bus, 14-bus, 15-bus, and 30-bus test systems. Furthermore, the results obtained using the proposed WOA are compared with those obtained by other up-to-date algorithms. The obtained results show the effectiveness of the proposed WOA to minimize the relay operating time for the optimal coordination of DOCRs.

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Hunting strategy and seasonality in the last interglacial occupation of Cueva Antón (Murcia, Spain)

Archaeological and Anthropological Sciences ◽

10.1007/s12520-018-0768-6 ◽

2019 ◽

Vol 11 (7) ◽

pp. 3577-3594 ◽

Cited By ~ 1

Author(s):

Montserrat Sanz ◽

Florent Rivals ◽

David García ◽

João Zilhão

Keyword(s):

Last Interglacial ◽

Hunting Strategy

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A prey–predator system with disease in prey and cooperative hunting strategy in predator

Journal of Physics A Mathematical and Theoretical ◽

10.1088/1751-8121/abbc7b ◽

2020 ◽

Vol 53 (48) ◽

pp. 485601

Author(s):

Sangeeta Saha ◽

G P Samanta

Keyword(s):

Cooperative Hunting ◽

Hunting Strategy ◽

Predator System ◽

Disease In Prey

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Nest usurpation and sequential nest occupation in the digger wasp Crabro monticola (Hymenoptera: Sphecidae)

Canadian Journal of Zoology ◽

10.1139/z82-124 ◽

1982 ◽

Vol 60 (5) ◽

pp. 921-925 ◽

Cited By ~ 14

Author(s):

John Alcock

Keyword(s):

Digger Wasp ◽

Apparent Reason ◽

Nest Usurpation

Females of Crabro monticola regularly abandoned the nests which they had been provisioning, sometimes for no apparent reason, sometimes because the nest had been entered in their absence by a conspecific usurper. After giving up her nest, a female had the option of digging a new nest or entering an already constructed burrow and usurping it from its owner, if it were occupied. Both options were exercised by members of the population. The result was that individual nests were held by as many as six different females over the course of 26 days. Each female occupied 2.2 nests on the average during the study. The adaptive advantages of nest usurpation and burrow switching are unclear. Nest usurpation attempts never resulted in joint occupation of a burrow in this species. Therefore, whatever its benefits, the entering strategy can evolve even if it does not lead to joint defense of a nest by its "communal" occupants.

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