by Katrina McIntosh, reptile keeper at the Buffalo Zoo
The Buffalo
Zoo shipped out over 1400 Puerto Rican crested toad tadpoles on November 19
2013 to be released back into the wild in Puerto Rico!
The Puerto Rican crested toad is an amazing amphibian! Within
24 hours after eggs are laid, tadpoles hatch and cling to their egg
strands. At this point they look like
swirly blobs. After another 12- 24 hours
pass, they become free-swimming tadpoles. They develop back legs within 10 days. Front legs appear a few days later. Shortly after developing these front legs, they will emerge from the
water and live on land. The tadpoles
still have a little of their tails left when they start living on land. They will absorb the remainder of these tails
within a day or two. Once they no longer
have tails they will start to eat smaller versions of what the adult toads
eat. This whole process takes about 21
days which is incredibly fast for an amphibian!
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| An emerging Puerto Rican Crested Toad tadpole. |
Since these tadpoles grow so quickly, every day they look
bigger and have new changes. As an animal keeper at the Zoo, it is
exciting to see the changes and watch them grow into toads. The Buffalo Zoo usually ships tadpoles around
a week after they hatch, so that they are still small enough to ship safely. We participate in a
Species Survival Plan (SSP) for this species.
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| An adult Puerto Rican crested toad. |
All of the tadpoles we released this year were from one set
of parents. The female is about 7 years
old and the male is 2 years old. A lot
of preparation is made for breeding these toads. First, the toads go through a cooling
cycle. This is where they are placed in
an area where they are cooled to 66
°F for about a month. This encourages the female to produce
eggs. Once they are done being cooled, they are then fed for a week straight. After they have had a week at their normal temperatures of 86
°F they are
then placed in a large tub that is half-full of water. This tub is set up 2 months prior to the
breeding to grow green algae which the tadpoles will eat. There are fake plants, ceramic pots, and
floating hide huts in these tubs to give the toads access to land areas and
lots of items for the female to lay her eggs around. We even set up a sprinkler to act as rain in
the tub. The toads tend to breed
during rain events in
Puerto Rico, so the rain
bar mimics rain. While the female lays her
eggs, the male rides around on her back fertilizing them through external
fertilization. Once all eggs are laid, the toads are removed from the tub and placed into tanks where they will be
feed daily for a week and monitored closely. The parents are removed so as not
to disturb the delicate eggs. Within 24 hours of the eggs being laid tadpoles
will hatch.
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| Katrina McIntosh packs tadpoles before shipping to Puerto Rico. |
Puerto Rican crested toads were nearly extinct by 1980 due
to habitat destruction and predation. As a result of conservation efforts and programs by zoos, there are now some stable
populations of these toads in the wild. It is very rewarding to work with this
program and to know that the Buffalo Zoo is doing our part to help save the
Puerto Rican crested toads.
