Experiment to determine lead effects on spermatophores
To the Save the Texas Blind Salamander Foundation,
As you must well know, the Texas Blind Salamander is only found in Hays County, Texas in the San Marcos Pool of the Edwards Aquifer. (3) It has come to my attention that there are some very dangerous pollutants in that area that may affect the reproductive abilities of this creature. I would very much like to receive a grant in order to investigate this possibility. Two of the major pollutants in Hays County are lead and nitric acid. (2) Rohr Inc. operating as goodrich in San Marcos, Texas releases 25 pounds of nitric acid into the air annually, which is a suspected skin or sense organ toxicant in humans. (6) The Texas-Lehigh cement Co. L.P. in buda, TX releases 12 pounds of lead into the air annually. (5) Lead is a recognized reproductive and deveopmental toxicant in humans. (4) Lead is the pollutant I have chosen to investigate in this study.
Reproduction in the Texas Blind Salamander occurs year-round. The male salamander deposits spermatophores on the surface of the pool which are then picked up by the female. (7) Lead from the air could potentially settle at the bottom of the very still San Marcos pools. The spermatophores would then be in direct contact with lead before they were picked up by the female. I would like to conduct an experiment to determine whether lead would harm the speratophores and therefore interfere with the reproductive system of the Texas Blind Salamander.
I will need to collect 21 salamanders for my study. Twenty will be female and one will be male. They will all be three years old and more than 3 cm long, since the salamanders that are smaller than this are less likely to breed. (7) If possible, the salamanders that are collected will be the same length. The male will be kept in a clean environment where he can deposit the spermatophores. Half of these spermatophores will be placed in a tank with lead deposits at the bottom of it. This is the independant variable placed on the experimental group. The other half will be placed in clean tanks. This is the control group. The exposure to lead will last for thirty minutes, an amount of time that reasonably might occur in nature. The female salamanders will randomly be assigned to two groups of ten salamanders each. The experimental group will have the lead-exposed spermatophores placed in their cloacas. I expect that the lead will have adsorbed into the gelatinous cap of the spermatophores by now. The control group will have the unexposed spermatophores placed in their cloacas . The females will lay eggs which will hatch. I will expect this experiment to take four months at the most, since it takes about 30 days for their eggs to hatch. (7) The dependant variable will be how many eggs are laid by the salamanders which hatch. I will measure this by counting baby salamanders. I expect that the spermatophores that were not exposed to lead will produce more hatched eggs.
