After visiting Carara, I took the ferry across the Culf of Nicoya to the Nicoya Peninsula to volunteer at the Cabo Blanco Absolute Natural Reserve at the southern tip of the peninsula. Cabo Blanco is in a transitional zone between dry and wet tropical forest, and was the first protected area in Costa Rica.

Mammals

The mantled howler monkeys (Alouatta palliata) proved easy to both see and hear as they moved around in the trees between the volunteer house where I was staying and the ranger station.

Mantled howler monkeys (Alouatta palliata). Howler monkeys get their name from the calls the males make to locate each other. They live in groups.

Once, when there was some construction going on at the ranger station using power tools, this set one of the howlers to call in response.

 
I saw this Panamanian white-faced capuchin (Cebus imitator) scavenging for food whilst walking a trail with another volunteer. Despite the rather anxious look on its face, it made no effort to run away, and carried on feeding whilst glancing at us.
 
Central American red brocket deer (Mazama temama) were mostly partly hidden by vegetation in the forest, but occasionally moved out into more open areas like the clearing beside the ranger station.
 

Central American agouti (Dasyprocta punctata).

In much of its range, the agouti is shy and hides from people, presumably because it is considered a delicacy. However here (and in other protected areas I visited) they come quite close to humans, like this agouti seen feeding just by the ranger station.

 

Variegated squirrel (Sciurus variegatoides rigidus).

Birds

Bare-throated tiger heron (Tigrisoma mexicanum).
 
Brown pelican (Pelecanus occidentalis).Flocks of twenty or thirty pelicans flew south across the bay in front of the volunteer house every late afternoon/early evening, presubly heading for a roost site.
 
Sandpiper (Calidris sp.) seen foraging on the shore at San Miguel Biological Station.
 

Rufous-backed wren (Campylorhynchus capistratus) taking a dust bath.

A few birds were seen in the more open, farmed habitats beside the road leading to the reserve.

Black-headed trogon (Trogon melanocephalus).
 

White-throated magpie-jay (Calocitta formosa).

The long-tailed manakin (Chiroxiphia linearis) inhabits both wet and dry tropical and subtropical forests.

Reptiles

Black spiny-tailed iguana (Ctenosaura similis).
 
Slender anole (Anolis limifrons).
 
Yellow-headed gecko (Gonatodes albogularis).

Southern rosebelly lizard (Sceloporus olloporus).

Insects

Leafcutter ants.
 
Tropical king skimmer (Orthemis sp.).

Executioner paper wasp (Polistes carnifex).

Unidentified dragonfly.

Other arthropods

A bark scorpion (Centruroides sp.) seen in our toilet.

The golden silk spider (Trichonephila clavipes) inhabits forests and wooded areas.

Hermit crabs on the beach.