Movement patterns of Tomistoma schlegelii in the Sekonyer Kanan river (Tanjung Puting National Park, Central Kalimantan, Indonesia): Preliminary range size estimates

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • René Bonke - , Zoologischen Forschungsmuseums Alexander Koenig (ZFMK) - Leibniz-Institut zur Analyse des Biodiversitätswandels (Autor:in)
  • Flora Ihlow - , Zoologischen Forschungsmuseums Alexander Koenig (ZFMK) - Leibniz-Institut zur Analyse des Biodiversitätswandels (Autor:in)
  • Wolfgang Böhme - , Zoologischen Forschungsmuseums Alexander Koenig (ZFMK) - Leibniz-Institut zur Analyse des Biodiversitätswandels (Autor:in)
  • Dennis Rödder - , Zoologischen Forschungsmuseums Alexander Koenig (ZFMK) - Leibniz-Institut zur Analyse des Biodiversitätswandels (Autor:in)

Abstract

Studies on home ranges and movement patterns have scarcely been conducted for crocodilians so far. Herein we present observations on movement patterns as preliminary home range size estimates for the endangered Tomistoma schlegelii (Crocodylia). Fieldwork was conducted at the Sekonyer Kanan River (Tanjung Puting National Park, Central Kalimantan, Indonesia). Three specimens were caught using a snare-pole, fitted with VHF radio tracking transmitters, and studied for a duration of two months between 31 August 2009 and 28 October 2009. Within this period, the individuals were relocated between 23 and 42 times, respectively. We analysed movement patterns by determining the animals' linear range sizes (LR), minimum convex polygon ranges (MCP), kernel density estimators (50% and 90% KDEs), and local a-convex hulls (50% and 90% LoCoH). Linear range sizes (LR) were 0.104, 0.276 and 0.739 km while minimum convex polygon sizes (100% MCP) were 0.1, 0.577 and 1.758 ha. The study animals' kernel range sizes (90% KDE) were 0.094, 0.663 and 2.08 ha. Core areas (50% KDE) were 0.02, 0.211 and 0.639 ha in size. Local a-convex hull range sizes (90% LoCoH) were 0.025, 0.323 and 0.821 ha whereby core areas (50% LoCoH) for two study animals measured 0.103 and 0.34 ha. Although, our study was limited to a single dry season and therefore likely underestimates full range sizes for the species - our results provide important baseline data for urgently required follow-up studies on movement patterns of this endangered crocodile species.

Details

OriginalspracheEnglisch
Seiten (von - bis)40-52
Seitenumfang13
FachzeitschriftSalamandra
Jahrgang50
Ausgabenummer1
PublikationsstatusVeröffentlicht - 2014
Peer-Review-StatusJa
Extern publiziertJa

Schlagworte

Schlagwörter

  • Activity patterns, Crocodylia, Kernel density estimator, Local convex hull, Minimum convex polygon, Radio telemetry