People

Félicie Dhellemmes

Postdoctoral Researcher

Behavioral Ecology
Biology

MPIB

 

Email:

 

Photo: SCIoI

← People Overview

Félicie Dhellemmes

Félicie Dhellemmes

Photo: SCIoI

Félicie Dhellemmes is a behavioral ecologist interested in the causes and consequences of consistent individual differences in behavior.

She joined SCIoI in September 2023 to work as a postdoctoral researcher.

During her PhD, Félicie investigated the role of individual differences in space use and fitness in juvenile lemon sharks in the Bahamas and previously also completed a postdoctoral position studying the spatial movements of pike in Northern Germany using acoustic telemetry.

At SCIoI, Félicie works on Project 51, where she investigates the interplay between the collective hunting behavior of icefishers and the collective evasion strategies of prey schools under the ice.

Projects

Félicie Dhellemmes is member of:

• Project 51: Navigating the explore-exploit trade off in collective search
6984777 Dhellemmes 1 apa 50 date desc year 19837 https://www.scienceofintelligence.de/wp-content/plugins/zotpress/
%7B%22status%22%3A%22success%22%2C%22updateneeded%22%3Afalse%2C%22instance%22%3Afalse%2C%22meta%22%3A%7B%22request_last%22%3A0%2C%22request_next%22%3A0%2C%22used_cache%22%3Atrue%7D%2C%22data%22%3A%5B%7B%22key%22%3A%22YEJQB3LT%22%2C%22library%22%3A%7B%22id%22%3A6984777%7D%2C%22meta%22%3A%7B%22creatorSummary%22%3A%22Bideau%20et%20al.%22%2C%22parsedDate%22%3A%222026-03-06%22%2C%22numChildren%22%3A1%7D%2C%22bib%22%3A%22%26lt%3Bdiv%20class%3D%26quot%3Bcsl-bib-body%26quot%3B%20style%3D%26quot%3Bline-height%3A%202%3B%20padding-left%3A%201em%3B%20text-indent%3A-1em%3B%26quot%3B%26gt%3B%5Cn%20%20%26lt%3Bdiv%20class%3D%26quot%3Bcsl-entry%26quot%3B%26gt%3BBideau%2C%20P.%2C%20Pham%2C%20D.%2C%20Dhellemmes%2C%20F.%2C%20Hansen%2C%20M.%2C%20%26amp%3B%20Krause%2C%20J.%20%282026%29.%20Watching%20Swarm%20Dynamics%20from%20Above%3A%20A%20Framework%20for%20Advanced%20Object%20Tracking%20in%20Drone%20Videos.%20%26lt%3Bi%26gt%3BInternational%20Journal%20of%20Computer%20Vision%26lt%3B%5C%2Fi%26gt%3B%2C%20%26lt%3Bi%26gt%3B134%26lt%3B%5C%2Fi%26gt%3B%284%29%2C%20146.%20%26lt%3Ba%20class%3D%26%23039%3Bzp-ItemURL%26%23039%3B%20href%3D%26%23039%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1007%5C%2Fs11263-025-02713-y%26%23039%3B%26gt%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1007%5C%2Fs11263-025-02713-y%26lt%3B%5C%2Fa%26gt%3B%26lt%3B%5C%2Fdiv%26gt%3B%5Cn%26lt%3B%5C%2Fdiv%26gt%3B%22%2C%22data%22%3A%7B%22itemType%22%3A%22journalArticle%22%2C%22title%22%3A%22Watching%20Swarm%20Dynamics%20from%20Above%3A%20A%20Framework%20for%20Advanced%20Object%20Tracking%20in%20Drone%20Videos%22%2C%22creators%22%3A%5B%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Pia%22%2C%22lastName%22%3A%22Bideau%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Duc%22%2C%22lastName%22%3A%22Pham%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22F%5Cu00e9licie%22%2C%22lastName%22%3A%22Dhellemmes%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Matthew%22%2C%22lastName%22%3A%22Hansen%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Jens%22%2C%22lastName%22%3A%22Krause%22%7D%5D%2C%22abstractNote%22%3A%22Easily%20accessible%20technologies%2C%20such%20as%20drones%20equipped%20with%20diverse%20onboard%20sensors%2C%20have%20greatly%20expanded%20opportunities%20to%20study%20animal%20behavior%20in%20natural%20environments.%20However%2C%20analyzing%20large%20volumes%20of%20unlabeled%20video%20data%2C%20often%20spanning%20hours%2C%20remains%20a%20significant%20challenge%20for%20machine%20learning%2C%20particularly%20in%20computer%20vision.%20Existing%20approaches%20typically%20process%20only%20a%20small%20number%20of%20frames%2C%20and%20accurate%20georeferencing%20of%20tracked%20positions%20is%20still%20largely%20unresolved%2C%20particularly%20in%20dynamic%20environments%20where%20static%20landmarks%20cannot%20be%20established.%20In%20this%20work%2C%20we%20focus%20on%20long-term%20tracking%20of%20animal%20behavior%20in%20real-world%20geographic%20coordinates.%20To%20address%20this%20challenge%2C%20we%20utilize%20classical%20probabilistic%20methods%20for%20state%20estimation%2C%20such%20as%20particle%20filtering.%20Particle%20filters%20offer%20a%20useful%20algorithmic%20structure%20for%20recursively%20adding%20new%20incoming%20information%20and%20thus%20ensuring%20time%20consistency.%20By%20incorporating%20recent%20developments%20in%20semantic%20object%20segmentation%2C%20we%20enable%20continuous%20tracking%20of%20rapidly%20evolving%20object%20formations%2C%20even%20in%20scenarios%20with%20limited%20data%20availability.%20We%20propose%20a%20novel%20approach%20for%20tracking%20schools%20of%20fish%20in%20the%20open%20ocean%20from%20drone%20videos.%20Our%20framework%20not%20only%20performs%20classical%20object%20tracking%20in%20image%20coordinates%2C%20instead%20it%20additionally%20tracks%20the%20position%20and%20spatial%20expansion%20of%20the%20fish%20school%20in%20geographic%20coordinates%20by%20fusing%20video%20data%20and%20the%20drone%5Cu2019s%20on%20board%20sensor%20information%20%28GPS%20and%20IMU%29.%20No%20landmarks%20with%20known%20geographic%20coordinates%20are%20required%2C%20making%20the%20proposed%20method%20adaptable%20to%20unstructured%2C%20dynamic%20environments%20like%20the%20open%20ocean%2C%20where%20static%20landmarks%20are%20unavailable.%20With%20this%2C%20the%20presented%20framework%20enables%20researchers%20to%20study%20the%20collective%20behavior%20of%20fish%20schools%20within%20their%20social%20and%20environmental%20context.%22%2C%22date%22%3A%222026-03-06%22%2C%22section%22%3A%22%22%2C%22partNumber%22%3A%22%22%2C%22partTitle%22%3A%22%22%2C%22DOI%22%3A%2210.1007%5C%2Fs11263-025-02713-y%22%2C%22citationKey%22%3A%22%22%2C%22url%22%3A%22https%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1007%5C%2Fs11263-025-02713-y%22%2C%22PMID%22%3A%22%22%2C%22PMCID%22%3A%22%22%2C%22ISSN%22%3A%221573-1405%22%2C%22language%22%3A%22en%22%2C%22collections%22%3A%5B%5D%2C%22dateModified%22%3A%222026-06-22T12%3A01%3A18Z%22%7D%7D%2C%7B%22key%22%3A%22G9DE8XYW%22%2C%22library%22%3A%7B%22id%22%3A6984777%7D%2C%22meta%22%3A%7B%22creatorSummary%22%3A%22Schakowski%20et%20al.%22%2C%22parsedDate%22%3A%222026%22%2C%22numChildren%22%3A1%7D%2C%22bib%22%3A%22%26lt%3Bdiv%20class%3D%26quot%3Bcsl-bib-body%26quot%3B%20style%3D%26quot%3Bline-height%3A%202%3B%20padding-left%3A%201em%3B%20text-indent%3A-1em%3B%26quot%3B%26gt%3B%5Cn%20%20%26lt%3Bdiv%20class%3D%26quot%3Bcsl-entry%26quot%3B%26gt%3BSchakowski%2C%20A.%2C%20Deffner%2C%20D.%2C%20Kavelaars%2C%20M.%20M.%2C%20Haux%2C%20L.%20M.%2C%20Kuroda%2C%20K.%2C%20Dhellemmes%2C%20F.%2C%20%26amp%3B%20Kurvers%2C%20R.%20H.%20J.%20M.%20%282026%29.%20Toward%20a%20psychology%20of%20real-life%20decision-making.%20%26lt%3Bi%26gt%3BTrends%20in%20Cognitive%20Sciences%26lt%3B%5C%2Fi%26gt%3B%2C%20S1364661326001610.%20%26lt%3Ba%20class%3D%26%23039%3Bzp-DOIURL%26%23039%3B%20href%3D%26%23039%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1016%5C%2Fj.tics.2026.07.003%26%23039%3B%26gt%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1016%5C%2Fj.tics.2026.07.003%26lt%3B%5C%2Fa%26gt%3B%26lt%3B%5C%2Fdiv%26gt%3B%5Cn%26lt%3B%5C%2Fdiv%26gt%3B%22%2C%22data%22%3A%7B%22itemType%22%3A%22journalArticle%22%2C%22title%22%3A%22Toward%20a%20psychology%20of%20real-life%20decision-making%22%2C%22creators%22%3A%5B%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Alexander%22%2C%22lastName%22%3A%22Schakowski%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Dominik%22%2C%22lastName%22%3A%22Deffner%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Marwa%20M.%22%2C%22lastName%22%3A%22Kavelaars%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Lou%20M.%22%2C%22lastName%22%3A%22Haux%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Kiri%22%2C%22lastName%22%3A%22Kuroda%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22F%5Cu00e9licie%22%2C%22lastName%22%3A%22Dhellemmes%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Ralf%20H.J.M.%22%2C%22lastName%22%3A%22Kurvers%22%7D%5D%2C%22abstractNote%22%3A%22%22%2C%22date%22%3A%228%5C%2F2026%22%2C%22section%22%3A%22%22%2C%22partNumber%22%3A%22%22%2C%22partTitle%22%3A%22%22%2C%22DOI%22%3A%2210.1016%5C%2Fj.tics.2026.07.003%22%2C%22citationKey%22%3A%22%22%2C%22url%22%3A%22https%3A%5C%2F%5C%2Flinkinghub.elsevier.com%5C%2Fretrieve%5C%2Fpii%5C%2FS1364661326001610%22%2C%22PMID%22%3A%22%22%2C%22PMCID%22%3A%22%22%2C%22ISSN%22%3A%2213646613%22%2C%22language%22%3A%22en%22%2C%22collections%22%3A%5B%5D%2C%22dateModified%22%3A%222026-08-20T07%3A40%3A38Z%22%7D%7D%2C%7B%22key%22%3A%227CDYW64D%22%2C%22library%22%3A%7B%22id%22%3A6984777%7D%2C%22meta%22%3A%7B%22creatorSummary%22%3A%22Bartashevich%20et%20al.%22%2C%22parsedDate%22%3A%222024-11-27%22%2C%22numChildren%22%3A2%7D%2C%22bib%22%3A%22%26lt%3Bdiv%20class%3D%26quot%3Bcsl-bib-body%26quot%3B%20style%3D%26quot%3Bline-height%3A%202%3B%20padding-left%3A%201em%3B%20text-indent%3A-1em%3B%26quot%3B%26gt%3B%5Cn%20%20%26lt%3Bdiv%20class%3D%26quot%3Bcsl-entry%26quot%3B%26gt%3BBartashevich%2C%20P.%2C%20Herbert-Read%2C%20J.%20E.%2C%20Hansen%2C%20M.%20J.%2C%20Dhellemmes%2C%20F.%2C%20Domenici%2C%20P.%2C%20Krause%2C%20J.%2C%20%26amp%3B%20Romanczuk%2C%20P.%20%282024%29.%20Collective%20anti-predator%20escape%20manoeuvres%20through%20optimal%20attack%20and%20avoidance%20strategies.%20%26lt%3Bi%26gt%3BCommunications%20Biology%26lt%3B%5C%2Fi%26gt%3B%2C%20%26lt%3Bi%26gt%3B7%26lt%3B%5C%2Fi%26gt%3B%281%29%2C%201586.%20%26lt%3Ba%20class%3D%26%23039%3Bzp-DOIURL%26%23039%3B%20href%3D%26%23039%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1038%5C%2Fs42003-024-07267-2%26%23039%3B%26gt%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1038%5C%2Fs42003-024-07267-2%26lt%3B%5C%2Fa%26gt%3B%26lt%3B%5C%2Fdiv%26gt%3B%5Cn%26lt%3B%5C%2Fdiv%26gt%3B%22%2C%22data%22%3A%7B%22itemType%22%3A%22journalArticle%22%2C%22title%22%3A%22Collective%20anti-predator%20escape%20manoeuvres%20through%20optimal%20attack%20and%20avoidance%20strategies%22%2C%22creators%22%3A%5B%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Palina%22%2C%22lastName%22%3A%22Bartashevich%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22James%20E.%22%2C%22lastName%22%3A%22Herbert-Read%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Matthew%20J.%22%2C%22lastName%22%3A%22Hansen%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22F%5Cu00e9licie%22%2C%22lastName%22%3A%22Dhellemmes%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Paolo%22%2C%22lastName%22%3A%22Domenici%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Jens%22%2C%22lastName%22%3A%22Krause%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22Pawel%22%2C%22lastName%22%3A%22Romanczuk%22%7D%5D%2C%22abstractNote%22%3A%22Abstract%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20The%20collective%20dynamics%20of%20self-organised%20systems%20emerge%20from%20the%20decision%20rules%20agents%20use%20to%20respond%20to%20each%20other%20and%20to%20external%20forces.%20This%20is%20evident%20in%20groups%20of%20animals%20under%20attack%20from%20predators%2C%20where%20understanding%20collective%20escape%20patterns%20requires%20evaluating%20the%20risks%20and%20rewards%20associated%20with%20particular%20social%20rules%2C%20prey%20escape%20behaviour%2C%20and%20predator%20attack%20strategies.%20Here%2C%20we%20find%20that%20the%20emergence%20of%20the%20%5Cu2018fountain%20effect%5Cu2019%2C%20a%20common%20collective%20pattern%20observed%20when%20animal%20groups%20evade%20predators%2C%20is%20the%20outcome%20of%20rules%20designed%20to%20maximise%20individual%20survival%20chances%20given%20predator%20hunting%20decisions.%20Using%20drone-based%20empirical%20observations%20of%20schooling%20sardine%20prey%20%28%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20Sardinops%20sagax%20caerulea%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%29%20attacked%20by%20striped%20marlin%20%28%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20Kajikia%20audax%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%29%2C%20we%20first%20find%20the%20majority%20of%20attacks%20produce%20fountain%20effects%2C%20with%20the%20dynamics%20of%20these%20escapes%20dependent%20on%20the%20predator%5Cu2019s%20attack%20direction.%20Then%2C%20using%20a%20spatially-explicit%20agent-based%20model%20of%20predator-prey%20dynamics%2C%20we%20show%20that%20fountain%20manoeuvres%20can%20emerge%20from%20combining%20an%20optimal%20individual%20prey%20escape%20angle%20with%20social%20interactions.%20The%20escape%20rule%20appears%20to%20prioritise%20maximising%20the%20distance%20to%20the%20predator%20and%20creates%20conflict%20in%20the%20effectiveness%20of%20predators%5Cu2019%20attacks%20and%20the%20prey%5Cu2019s%20avoidance%2C%20explaining%20the%20empirically%20observed%20predators%5Cu2019%20attack%20strategies%20and%20the%20fountain%20evasions%20produced%20by%20prey.%20Overall%2C%20we%20identify%20the%20proximate%20and%20ultimate%20explanations%20for%20fountain%20effects%20and%20more%20generally%20highlight%20that%20the%20collective%20patterns%20of%20self-organised%20predatory-prey%20systems%20can%20be%20understood%20by%20considering%20both%20social%20escape%20rules%20and%20attack%20strategies.%22%2C%22date%22%3A%222024-11-27%22%2C%22section%22%3A%22%22%2C%22partNumber%22%3A%22%22%2C%22partTitle%22%3A%22%22%2C%22DOI%22%3A%2210.1038%5C%2Fs42003-024-07267-2%22%2C%22citationKey%22%3A%22%22%2C%22url%22%3A%22https%3A%5C%2F%5C%2Fwww.nature.com%5C%2Farticles%5C%2Fs42003-024-07267-2%22%2C%22PMID%22%3A%22%22%2C%22PMCID%22%3A%22%22%2C%22ISSN%22%3A%222399-3642%22%2C%22language%22%3A%22en%22%2C%22collections%22%3A%5B%5D%2C%22dateModified%22%3A%222026-08-20T06%3A52%3A30Z%22%7D%7D%2C%7B%22key%22%3A%22F2DL6QW5%22%2C%22library%22%3A%7B%22id%22%3A6984777%7D%2C%22meta%22%3A%7B%22creatorSummary%22%3A%22Pacher%20et%20al.%22%2C%22parsedDate%22%3A%222024%22%2C%22numChildren%22%3A2%7D%2C%22bib%22%3A%22%26lt%3Bdiv%20class%3D%26quot%3Bcsl-bib-body%26quot%3B%20style%3D%26quot%3Bline-height%3A%202%3B%20padding-left%3A%201em%3B%20text-indent%3A-1em%3B%26quot%3B%26gt%3B%5Cn%20%20%26lt%3Bdiv%20class%3D%26quot%3Bcsl-entry%26quot%3B%26gt%3BPacher%2C%20K.%2C%20Krause%2C%20J.%2C%20Bartashevich%2C%20P.%2C%20Romanczuk%2C%20P.%2C%20Bideau%2C%20P.%2C%20Pham%2C%20D.%2C%20Burns%2C%20A.%20L.%2C%20Deffner%2C%20D.%2C%20Dhellemmes%2C%20F.%2C%20Binder%2C%20B.%2C%20Boswell%2C%20K.%20M.%2C%20Galv%26%23xE1%3Bn%26%23x2010%3BMaga%26%23xF1%3Ba%2C%20F.%2C%20Domenici%2C%20P.%2C%20%26amp%3B%20Hansen%2C%20M.%20J.%20%282024%29.%20Evidence%20for%20a%20by%26%23x2010%3Bproduct%20mutualism%20in%20a%20group%20hunter%20depends%20on%20prey%20movement%20state.%20%26lt%3Bi%26gt%3BFunctional%20Ecology%26lt%3B%5C%2Fi%26gt%3B%2C%20%26lt%3Bi%26gt%3B38%26lt%3B%5C%2Fi%26gt%3B%2810%29%2C%202123%26%23x2013%3B2138.%20%26lt%3Ba%20class%3D%26%23039%3Bzp-DOIURL%26%23039%3B%20href%3D%26%23039%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1111%5C%2F1365-2435.14638%26%23039%3B%26gt%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1111%5C%2F1365-2435.14638%26lt%3B%5C%2Fa%26gt%3B%26lt%3B%5C%2Fdiv%26gt%3B%5Cn%26lt%3B%5C%2Fdiv%26gt%3B%22%2C%22data%22%3A%7B%22itemType%22%3A%22journalArticle%22%2C%22title%22%3A%22Evidence%20for%20a%20by%5Cu2010product%20mutualism%20in%20a%20group%20hunter%20depends%20on%20prey%20movement%20state%22%2C%22creators%22%3A%5B%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22K.%22%2C%22lastName%22%3A%22Pacher%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22J.%22%2C%22lastName%22%3A%22Krause%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22P.%22%2C%22lastName%22%3A%22Bartashevich%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22P.%22%2C%22lastName%22%3A%22Romanczuk%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22P.%22%2C%22lastName%22%3A%22Bideau%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22D.%22%2C%22lastName%22%3A%22Pham%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22A.%20L.%22%2C%22lastName%22%3A%22Burns%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22D.%22%2C%22lastName%22%3A%22Deffner%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22F.%22%2C%22lastName%22%3A%22Dhellemmes%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22B.%22%2C%22lastName%22%3A%22Binder%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22K.%20M.%22%2C%22lastName%22%3A%22Boswell%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22F.%22%2C%22lastName%22%3A%22Galv%5Cu00e1n%5Cu2010Maga%5Cu00f1a%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22P.%22%2C%22lastName%22%3A%22Domenici%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22M.%20J.%22%2C%22lastName%22%3A%22Hansen%22%7D%5D%2C%22abstractNote%22%3A%22Abstract%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20Group%5Cu2010hunting%20animals%20have%20been%20shown%20to%20engage%20their%20prey%20in%20long%20pursuits%20%28kms%29%20to%20increase%20capture%20success%2C%20but%20the%20evidence%20for%20this%20is%20limited%20to%20a%20few%20terrestrial%20species.%20This%20predation%20strategy%20may%20be%20effective%20in%20the%20open%5Cu2010ocean%2C%20where%20group%5Cu2010hunts%20are%20characterised%20by%20large%20predator%5Cu2013prey%20size%20ratios%20and%20there%20are%20few%20places%20for%20prey%20to%20hide.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20However%2C%20recording%20the%20attack%20rates%2C%20capture%20rates%20and%20capture%20success%20probabilities%20of%20grouping%20predators%20during%20long%5Cu2010distance%20pursuits%20through%20the%20open%20ocean%2C%20remains%20a%20significant%20challenge.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20Here%20we%20use%20a%20combination%20of%20underwater%20and%20aerial%20video%20to%20assess%20the%20attack%20and%20capture%20behaviour%20of%20striped%20marlin%2C%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20Kajikia%20audax%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%2C%20in%20relation%20to%20the%20movement%20of%20their%20schooling%20prey%20%28%5Cu2018stationary%5Cu2019%20and%20%5Cu2018mobile%5Cu2019%20movement%20states%29%20during%20group%20hunts.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20We%20found%20that%20the%20attack%20rate%20was%20higher%20when%20the%20prey%20school%20was%20%5Cu2018stationary%5Cu2019%20and%2C%20during%20these%20times%2C%20individual%20marlin%20could%20make%20longer%20sequences%20of%20uninterrupted%20attacks%20on%20the%20prey%20school%2C%20effectively%20monopolising%20the%20prey%20resource%20for%20short%20periods%20over%20conspecifics.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20When%20the%20prey%20school%20was%20%5Cu2018mobile%5Cu2019%2C%20the%20attack%20pattern%20changed%20and%20individual%20marlin%20alternated%20their%20attacks%20on%20the%20prey%20school%20more%20frequently.%20Capture%20success%20probability%20%28likelihood%20of%20capture%20per%20attack%29%20was%20not%20affected%20by%20prey%20movement%20state.%20However%2C%20attacks%20on%20%5Cu2018mobile%5Cu2019%20schools%20resulted%20in%20more%20prey%20fish%20becoming%20isolated%20from%20the%20school%2C%20and%20these%20isolated%20prey%20were%20easily%20captured%5Cu2014not%20by%20the%20attacker%20but%20by%20conspecifics%20swimming%20nearby.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20The%20likelihood%20of%20a%20prey%20becoming%20isolated%20from%20a%20%5Cu2018mobile%5Cu2019%20school%20was%20predicted%20by%20prey%20school%20speed%2C%20with%20a%200.1%5Cu2009m%5Cu2009s%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cu22121%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20increase%20leading%20to%20an%2018.01%25%20increase%20in%20the%20chance%20of%20isolation.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20Altogether%20this%20meant%20the%20capture%20rate%20at%20the%20group%20level%20was%20highest%20when%20the%20prey%20school%20was%20%5Cu2018mobile%5Cu2019%20rather%20than%20%5Cu2018stationary%5Cu2019%20because%20the%20predators%20that%20were%20pursuing%20the%20%5Cu2018mobile%5Cu2019%20prey%20school%20had%20an%20increased%20availability%20of%20isolated%20and%20easy%20to%20capture%20prey.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20This%20mechanism%20provides%20evidence%20for%20a%20by%5Cu2010product%20mutualism%20selecting%20for%20conspecific%20group%20formation%20and%20we%20discuss%20our%20findings%20in%20consideration%20of%20the%20social%20structure%20of%20the%20hunting%20group%20and%20the%20type%20of%20prey.%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20Read%20the%20free%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20Plain%20Language%20Summary%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20for%20this%20article%20on%20the%20Journal%20blog.%22%2C%22date%22%3A%2210%5C%2F2024%22%2C%22section%22%3A%22%22%2C%22partNumber%22%3A%22%22%2C%22partTitle%22%3A%22%22%2C%22DOI%22%3A%2210.1111%5C%2F1365-2435.14638%22%2C%22citationKey%22%3A%22%22%2C%22url%22%3A%22https%3A%5C%2F%5C%2Fbesjournals.onlinelibrary.wiley.com%5C%2Fdoi%5C%2F10.1111%5C%2F1365-2435.14638%22%2C%22PMID%22%3A%22%22%2C%22PMCID%22%3A%22%22%2C%22ISSN%22%3A%220269-8463%2C%201365-2435%22%2C%22language%22%3A%22en%22%2C%22collections%22%3A%5B%5D%2C%22dateModified%22%3A%222026-08-20T06%3A55%3A37Z%22%7D%7D%2C%7B%22key%22%3A%22MB4CCKS4%22%2C%22library%22%3A%7B%22id%22%3A6984777%7D%2C%22meta%22%3A%7B%22creatorSummary%22%3A%22Hansen%20et%20al.%22%2C%22parsedDate%22%3A%222022-10-31%22%2C%22numChildren%22%3A1%7D%2C%22bib%22%3A%22%26lt%3Bdiv%20class%3D%26quot%3Bcsl-bib-body%26quot%3B%20style%3D%26quot%3Bline-height%3A%202%3B%20padding-left%3A%201em%3B%20text-indent%3A-1em%3B%26quot%3B%26gt%3B%5Cn%20%20%26lt%3Bdiv%20class%3D%26quot%3Bcsl-entry%26quot%3B%26gt%3BHansen%2C%20M.%20J.%2C%20Krause%2C%20S.%2C%20Dhellemmes%2C%20F.%2C%20Pacher%2C%20K.%2C%20Kurvers%2C%20R.%20H.%20J.%20M.%2C%20Domenici%2C%20P.%2C%20%26amp%3B%20Krause%2C%20J.%20%282022%29.%20Mechanisms%20of%20prey%20division%20in%20striped%20marlin%2C%20a%20marine%20group%20hunting%20predator.%20%26lt%3Bi%26gt%3BCommunications%20Biology%26lt%3B%5C%2Fi%26gt%3B%2C%20%26lt%3Bi%26gt%3B5%26lt%3B%5C%2Fi%26gt%3B%281%29%2C%201161.%20%26lt%3Ba%20class%3D%26%23039%3Bzp-DOIURL%26%23039%3B%20href%3D%26%23039%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1038%5C%2Fs42003-022-03951-3%26%23039%3B%26gt%3Bhttps%3A%5C%2F%5C%2Fdoi.org%5C%2F10.1038%5C%2Fs42003-022-03951-3%26lt%3B%5C%2Fa%26gt%3B%26lt%3B%5C%2Fdiv%26gt%3B%5Cn%26lt%3B%5C%2Fdiv%26gt%3B%22%2C%22data%22%3A%7B%22itemType%22%3A%22journalArticle%22%2C%22title%22%3A%22Mechanisms%20of%20prey%20division%20in%20striped%20marlin%2C%20a%20marine%20group%20hunting%20predator%22%2C%22creators%22%3A%5B%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22M.%20J.%22%2C%22lastName%22%3A%22Hansen%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22S.%22%2C%22lastName%22%3A%22Krause%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22F.%22%2C%22lastName%22%3A%22Dhellemmes%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22K.%22%2C%22lastName%22%3A%22Pacher%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22R.%20H.%20J.%20M.%22%2C%22lastName%22%3A%22Kurvers%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22P.%22%2C%22lastName%22%3A%22Domenici%22%7D%2C%7B%22creatorType%22%3A%22author%22%2C%22firstName%22%3A%22J.%22%2C%22lastName%22%3A%22Krause%22%7D%5D%2C%22abstractNote%22%3A%22Abstract%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20Many%20terrestrial%20group-hunters%20cooperate%20to%20kill%20prey%20but%20then%20compete%20for%20their%20share%20with%20dominance%20being%20a%20strong%20predictor%20of%20prey%20division.%20In%20contrast%2C%20little%20is%20known%20about%20prey%20division%20in%20group-hunting%20marine%20predators%20that%20predominately%20attack%20small%2C%20evasive%20prey%20%28e.g.%20fish%20schools%29.%20We%20identified%20individual%20striped%20marlin%20%28%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20Kajikia%20audax%5Cn%20%20%20%20%20%20%20%20%20%20%20%20%20%20%29%20hunting%20in%20groups.%20Groups%20surrounded%20prey%20but%20individuals%20took%20turns%20attacking.%20We%20found%20that%20competition%20for%20prey%20access%20led%20to%20an%20unequal%20division%20of%20prey%20among%20the%20predators%2C%20with%2050%25%20of%20the%20most%20frequently%20attacking%20marlin%20capturing%2070%5Cu201380%25%20of%20the%20fish.%20Neither%20aggression%2C%20body%20size%20nor%20variation%20in%20hunting%20efficiency%20explained%20this%20skewed%20prey%20division.%20We%20did%20find%20that%20newly%20arrived%20groups%20of%20marlin%20gained%20on%20average%20more%20access%20to%20the%20prey.%20This%20raises%20the%20possibility%20that%20newly%20arrived%20marlin%20were%20hungrier%20and%20more%20motivated%20to%20feed.%20However%2C%20this%20result%20does%20not%20necessarily%20explain%20the%20unequal%20prey%20division%20among%20the%20predators%20because%20the%20skew%20in%20prey%20captures%20was%20found%20at%20the%20level%20of%20these%20groups.%20Dynamic%20prey%20division%20is%20probably%20widespread%20but%20under-reported%20in%20marine%20group-hunters%20and%20the%20inability%20of%20individuals%20to%20monopolize%20prey%20until%20satiation%20likely%20reduces%20the%20importance%20of%20social%20hierarchies%20for%20prey%20division.%22%2C%22date%22%3A%222022-10-31%22%2C%22section%22%3A%22%22%2C%22partNumber%22%3A%22%22%2C%22partTitle%22%3A%22%22%2C%22DOI%22%3A%2210.1038%5C%2Fs42003-022-03951-3%22%2C%22citationKey%22%3A%22%22%2C%22url%22%3A%22https%3A%5C%2F%5C%2Fwww.nature.com%5C%2Farticles%5C%2Fs42003-022-03951-3%22%2C%22PMID%22%3A%22%22%2C%22PMCID%22%3A%22%22%2C%22ISSN%22%3A%222399-3642%22%2C%22language%22%3A%22en%22%2C%22collections%22%3A%5B%5D%2C%22dateModified%22%3A%222026-06-29T10%3A40%3A30Z%22%7D%7D%5D%7D
Bideau, P., Pham, D., Dhellemmes, F., Hansen, M., & Krause, J. (2026). Watching Swarm Dynamics from Above: A Framework for Advanced Object Tracking in Drone Videos. International Journal of Computer Vision, 134(4), 146. https://doi.org/10.1007/s11263-025-02713-y
Schakowski, A., Deffner, D., Kavelaars, M. M., Haux, L. M., Kuroda, K., Dhellemmes, F., & Kurvers, R. H. J. M. (2026). Toward a psychology of real-life decision-making. Trends in Cognitive Sciences, S1364661326001610. https://doi.org/10.1016/j.tics.2026.07.003
Bartashevich, P., Herbert-Read, J. E., Hansen, M. J., Dhellemmes, F., Domenici, P., Krause, J., & Romanczuk, P. (2024). Collective anti-predator escape manoeuvres through optimal attack and avoidance strategies. Communications Biology, 7(1), 1586. https://doi.org/10.1038/s42003-024-07267-2
Pacher, K., Krause, J., Bartashevich, P., Romanczuk, P., Bideau, P., Pham, D., Burns, A. L., Deffner, D., Dhellemmes, F., Binder, B., Boswell, K. M., Galván‐Magaña, F., Domenici, P., & Hansen, M. J. (2024). Evidence for a by‐product mutualism in a group hunter depends on prey movement state. Functional Ecology, 38(10), 2123–2138. https://doi.org/10.1111/1365-2435.14638
Hansen, M. J., Krause, S., Dhellemmes, F., Pacher, K., Kurvers, R. H. J. M., Domenici, P., & Krause, J. (2022). Mechanisms of prey division in striped marlin, a marine group hunting predator. Communications Biology, 5(1), 1161. https://doi.org/10.1038/s42003-022-03951-3

Research

An overview of our scientific work

See our Research Projects