Tours of the Galapagos Islands were included in our Ecoventura cruise on the M/Y Letty. After landing in Puerto Ayora, Isla Santa Cruz, we traveled by bus for 45 minutes to the Santa Cruz highlands.
 |
 |
 |
| Photographing a Galapagos giant tortoise |
| Photo © Barb & Ron Kroll |
At Rancho Primicias, a reserve for giant tortoises, we exchanged our running shoes for rubber boots so we could walk through the tall grass looking for wild tortoises.
They were not hard to find. Scattered like boulders in the greenery, Galapagos giant tortoises (scientific name: Chelonoidis nigra, formerly Geochelone elephantopus) grow up to 500 pounds (230 kilograms).
Tortoise shells
We stopped at a pavilion where our Galapagos cruise guide, Yvonne Mortola, showed us an empty tortoise shell so heavy that we could barely pry one end off the ground. "Tortoise shells are made from bone and go all the way around the giant tortoise," she described.
 |
 |
 |
| Visitor fits inside a giant tortoise shell. |
| Photo © Barb & Ron Kroll |
"Tortoises can't go in and out of their shells. That only happens in cartoons," she said. "Keratin, the substance our nails are made of, protects their bone shells."
Shells of the Santa Cruz subspecies (porteri) of Galapagos tortoises have domed shells. "The top of the shell is called the carapace and the bottom is called the plastrium," explained Yvonne. "Males have concave plastriums so they can mate."
Galapagos tortoise facts
To give us an idea of the size of a giant tortoise shell, Ceci Guerrero, another expert guide on our Galapagos cruise, invited one of M/Y Letty's petite female passengers to crawl inside. She fit.
Ceci dispelled some myths about Galapagos tortoises. "You can't tell the age of a tortoise by counting the growth rings."
 |
 |
 |
| Visitors can get close to Galapagos giant tortoises. |
| Photo © Barb & Ron Kroll |
Giant tortoises grow quickly in the first 20 years. "The number of rings depends on whether the climate is wet or dry," she added. "Tortoises die with the same number of plates (scutes) in their shells as they are born with. The plates get bigger as the tortoise grows."
Tortoise behavior
Our Galapagos guides advised us to approach the wild tortoises from behind, rather than in front. "If you walk toward them, you will hear hissing," said Ceci.
"Don't be afraid. The giant tortoises are just exhaling air quickly so they can make room to pull in their heads and protect them behind their front legs."
 |
 |
 |
| Scales and claws on leg |
| Photo © Barb & Ron Kroll |
Yvonne Mortola noted that the Galapagos tortoises have no mobility, other than for mating and eating. "If a tick is making a giant tortoise itchy behind his ear, he is unable scratch it. Instead, he invites mockingbirds and finches to pick off the ticks by stretching up from the ground and lifting his head. The birds get a free meal and the tortoise is happy."
Giant tortoise photos
We loved our close-up encounters with Galapagos tortoises. Our close proximity allowed us to examine the leathery scales on their legs and the claws on their feet (five on the front legs and four on the back).
We photographed the giant tortoises as they followed "tortoise highways" or paths. With their battered shells, wrinkled necks and hide, they looked incredibly ancient. (Galapagos tortoises can live for more than 150 years.)
 |
 |
 |
| Adult Galapagos giant tortoise eats grass. |
| Photo © Barb & Ron Kroll |
Tortoise diet
As we watched the Galapagos tortoises munch the lush green grass, Yvonne Mortola asked us to look at their mouths. "Tortoises have no teeth. Instead they have a sharp horn plate."
Digestion takes one to three weeks, depending on what the tortoises eat. Yvonne explained that on Espanola Island, one species of prickly pear cactus did not recover after the 14 remaining Espanola tortoises were brought to the Charles Darwin Research Station in Santa Cruz, even after invasive goats were eliminated in 1975.
"They later discovered that the cactus seeds only germinated after they passed through the digestive systems of the giant tortoises."
Mating and egg-laying
 |
 |
 |
| Wallowing in mud |
| Photo © Barb & Ron Kroll |
Our Galapagos guides explained that giant tortoises reach sexual maturity when they are 15 to 20 years old. In February, female tortoises migrate to the drier lowlands.
Males mate with them, then return to the Santa Cruz highlands in April. The females stay in the lowlands to lay their eggs.
"Between February and June, we don't see many tortoises here in Rancho Primicias reserve," noted Yvonne. "We see lots of giant tortoises now, because it is October."
Some of the wild tortoises wallowed with great pleasure in mud baths. (Mud protects them from parasites and helps regulate body temperature.)
One of the Galapagos tortoises stretched out his wizened old face. It was only then that we realized why he looked familiar. He had a striking resemblance to Stephen Spielberg's ET.
TRAVEL INFORMATION
Ecoventura: www.ecoventura.com
Copa Airlines: www.copaair.com
Ecuador Ministry of Tourism: www.ecuador.travel
More things to see & do in the Galapagos Islands:
Genovesa Island Galapagos - Doves, Red-Footed Boobies and Short-Eared Owls
Darwin Bay Tower Island Galapagos - What to See
North Seymour Galapagos Trip - Land Iguanas and Magnificent Frigatebirds
Santa Cruz Island Galapagos - Lava Tubes and Pit Craters
Bartolome and Pinnacle Rock Galapagos Cruise Tour
