Iguana Island Wildlife Refuge
PedasÃ, Gulf of Panama, Eastern Tropical Pacific Ocean
Station 13:
The Rocky Coast
Location
As you leave the path you will see a rocky promontory on your right above the rest. Climb up and look around for a spectacular view of one of the earwig nesting sites.
This is another good spot for a group photo, whether overlooking the nesting and rocky coastline, El Cirial beach, or the open sea.
95% of the island's coastline is made up of rocky coastlines
Now look to your right and you will see a long channel between the rocks through which the waves penetrate, whose profile allows you to describe the rocky coastlines that surround the island.
95% of the island's coast is composed of basalt, forming a strong rocky coastline, which, when the tide recedes, allows the formation of large tide pools. The dominant animals are crabs and molluscs. The coastal areas (covered by high tide) are dominated by crabs, which feed on the algae attached to the rocks; while the armored crab is rare to find in this area. In the upper areas, outside the range of the tide, is the mangote crab, which also frequents the wooded areas of the island. Their populations have decreased significantly due to hunting.
Tide pools are teeming with life
Now go down to the open sea. In the rock you will find a natural staircase. From this platform, at low tide you will see tide pools.
The tide pools are inhabited by small fish, snails, algae and nudibranchs (shellless molluscs that resemble slugs). Many of them never leave this habitat, while others only inhabit it during their juvenile stage, and then migrate to the adjacent rocky and coral bottoms. All its inhabitants are very special organisms, as they are adapted to the most hostile environment of the island's habitats, due to the sudden changes that occur in a very short time. When the tide recedes, the temperature and salinity rise very quickly due to the action of the sun and the evaporation of water, while oxygen decreases; when the tide comes in, the process is reversed, as they are invaded by fresh seawater.
The shape of the abdomen distinguishes the sex of crabs
The females have a rounded abdomen, which allows them to carry the eggs.
The male has a pointed abdomen.
Having an external skeleton, crabs are forced to shed their shell when they no longer fit inside it.
Search the rocky shoreline for dry shells and identify if it was molted by a female or a male. Handle them with care, they are very fragile.