here’s part two of my trip report / photo album for the biological excursion to costa rica.
previous parts:
part two started with a visit to doña christina’s medicinal garden “la aroma-tica”, in la fortuna. on an area of 2.500 square meters, she and her family run a “finca integral” (organic farm) and cultivate tea, herbs, medicinal and pharmaceutic plants.
it’s always fascinating to see what different plants are used for, traditionally and recently – from natural fabric dyes to cancer treatment.
next up was a hike around different succession stages of vegetation around the arenal volcano – the youngest and most active volcano in costa rica. we didn’t experience any earthquakes or lava flowing, but it was still impressive to walk through an area with large patches completely destroyed as recently as 20 years ago. even more impressive is how the rainforest steadily reclaims these areas.
two notable, very impressive plants we saw along the way:
- the guarumo tree (cecropia obtusifolia) , also known as the “ant tree”, is host to symbiotic ants, which receive free accommodation inside the hollow stems. in return, the vicious azteca ants (azteca sp.) protect the tree and attack virtually anything.
- the kapok tree (ceiba pentandra) is a different caliber: it’s one of the giants of the rainforest and grows up to 75 meters high. that’s abut twice as high as most other trees in the rainforest. it forms massive buttress roots for mechanical stability, and is home to many animals and other plants.
the arenal hanging bridges are another destination that you shouldn’t miss when in the area. it’s a private nature reserve with nature trails and 16 bridges (up to 98 meters long), which allow you to experience the part of the rainforest that hosts up to two thirds of the entire rainforest biodiversity: the canopy.
on our way down south, we made a short but very memorable stop at a local fruit stand, and got to try pretty much all the tropical fruits they had in stock: different kinds of mangos, cashew nuts and their edible fruit stalks, malay apples, star apples, soursop, fresh pineapples, sapodilla, passion fruit, …
as usual, german captions and additional info are available in the photo gallery: volcan arenal, hanging bridges and tropical fruit

dona christina presents plants from her medicinal garden “la aroma-tica”, near la fortuna

giant granadilla (passiflora quadrangularis). the plant forms pseudo-eggs that make butterflies think there are already enough eggs on that stalk.

guarumo (cecropia obtusifolia), a tree with symbiotic azteca ants

black pepper (piper nigrum)

aloe vera

a peeled leaf of aloe vera. the gelatinous mass is edible (though very slimy!).

dona christina prepares tea with fresh sugarcane sticks

zingiber sp., flower

volcan arenal

sopralia sp., a pioneer orchid

walking along the foot of the volcano, through cana brava (gynerium sagittatum) thicket

hiking around volcan arenal

a young guarumo tree (cecropia obtusifolia)

guarumo (cecropia obtusifolia) builds hollow stems that are home to symbiotic azteca ants which defend the plant against herbivores

hollow chambers in cecropia obtusifola, perfect ant nests

epidendrum radicans, another pioneer orchid

sopralia sp., the orchid genus with the biggest flowers

white-headed capuchin monkey (cebus capucinus) in the tropical rainforest near volcan arenal

white-headed capuchin monkey (cebus capucinus) in the tropical rainforest near volcan arenal

tropical rainforest near volcan arenal

a flowering liana of the bignoniaceae family (ramiflory)

a flowering liana of the bignoniaceae family (ramiflory)

perfectly camouflaged norops lizard (anolis sp. or norops sp.)

group photo at a giant kapok tree (ceiba pentandra)

panorama: group photo at a giant kapok tree (ceiba pentandra)

lunchbreak at volcan arenal’s lava field of 1992

area of high volcanic activity, no trespassing.

volcan arenal and i

hdr panorama: volcan arenal and surroundings

arenal hanging bridges through the tropical rainforest

“bird!”

a kolibri’s empty nest

leafcutter ants (atta cf cephalotes) – note especially the little guards sitting on top of the leaf segments!

a micro-orchid (?) in the canopy

vertical panorama: arenal hanging bridges and below

arenal hanging bridges through the rainforest canopy

arenal hanging bridges through the rainforest canopy

late evening in the rainforest of the hanging bridges

baby gecko cleaning its eye

you can tell from the facial expressions that we were all (1) carnivores and (2) very hungry.

dinner: a giant costa rican steak not far from the volcano

a brown-throated sloth (bradypus variegatus) is sleeping on a cecropia tree (cecropia sp.)

montezuma oropendola (psarocolius montezuma) and woven hanging nests

montezuma oropendola (psarocolius montezuma) and woven hanging nests

old electrical stove

typical costa rican living room

tropical fruit stand, somewhere in costa rica

tropical fruit: bananas (musa sp.)

tropical fruit: cashew nuts (anacardium occidentale, brownish) with edible, thickened fruit stalks

tropical fruit: green and red mangos (mangifera indica)

tropical fruit: malay apples (syzygium malaccense)

tropical fruit: star apples (chrysophyllum cainito)

tropical fruit: star apples (chrysophyllum cainito), soursop (annona muricata), papayas (carica papaya), malay apples (syzygium malaccense) and mandarins (citrus reticul

tropical fruit: cashew nuts (anacardium occidentale, brownish) with edible, thickened fruit stalks

tropical fruit: pineapples (ananas comosus)

firewood dried bananas

tropical fruit stand: green mangos (mangifera indica), cashew nuts (anacardium occidentale) and a broken knife

tropical fruit: sapodilla, bully tree fruit (manilkara zapota)

tropical fruit: yellow-red mangos (mangifera indica)

american crocodile (crocodylus acutus)

american crocodile (crocodylus acutus)

american crocodile (crocodylus acutus)

supermarket “dos pinos” in dominical – the shelves were really that skew