No, the kodkod is not nocturnal. Under observation they were as likely to be as active during the day as at night. For example, a male kodkod was seen hunting during the daytime from a forest edge, preying on free-ranging young chickens in a nearby field according to Mel and Fiona Sunquist in their book Wild Cats of the World.
The Sunquists were referring to 5 male kodkods who were radio collared by Jim Sanderson, a small wild cat specialist. He studied the kodkod on Chiloé Island off the coast of Chile for six months in 1997-1998. The cats he studied made some long-distance movements shortly before dawn or just after sunset. And they made long-distance movements during the daytime under the cover of vegetation.
They state that one male kodkod travelled 5 km during an evening. Another male was observed crossing a road during the daytime, in the late afternoon, when the road was in shade from the trees lining the road.
The kodkods observed had night-time rest sites in thick piles of live or dead vegetation and daytime rest sites in dense vegetation in ravines. The rest sites were also along streams with heavy cover and in piles of dead gorse.
The conclusion is that kodkods hunt during the day and at dawn and dusk, and also at night. Their behavior reminds me of the domestic cat when allowed outside. Jim Sanderson worked with Mel Sunquist and A.W. Iriarte in reporting on kodkod behavior as written up in their Natural history and landscape-use of guignas (Oncifelis guigna) on Isla Grande Chiloé, Chile and published in J. Mammal.
P.S. ‘Kodkod’ is name given to the species by the Araucanian Indians. In Chile and Argentina, this cat is normally called ‘guiña’. Wikipedia uses the Latin name (scientific name) Leopardus guigna while my reference book uses Oncifelis guigna. Clearly there has been a change in the taxonomy of this small wild cat since the publication of Wild Cats of the World in 2002.
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