The Natural History of the Media Luna Watershed

Preface

From Richard:

I have been exploring the Rio Verde region for nearly twenty years with my good friend, Oceanographer and Master Scuba Diver Trainer, Ossiel Martinez. As a field biologist, I became frustrated with the lack of nature guidebooks for the Rio Verde region. I’ve always taken at least twenty pounds of nature reference books and guides of similar semiarid areas with hopes of finding the bird, plant, fish, snake, turtle or other critters that I observed in the Rio Verde area. Finally, I decided to make it simpler for people interested in learning about the region by composing a simple guide to the aquatic natural history of the Rio Verde area within the Media Luna Watershed.

The entire Media Luna Watershed is an uncommon territory due to its aquatic nature found within semiarid conditions (25 to 51 cm of annual precipitation). The Media Luna Watershed averages 50 cm per year. The entire watershed is a rare oasis of life surrounded by fields of citrus trees and various other crops: nourished by the waters from the Media Luna springs.

In this book, I provide a straightforward description of the Media Luna Watershed and what makes it such a valuable and unique ecosystem. I dedicate this book to all the foreign visitors and local citizens who are looking for their personal discoveries and adventures within the Media Luna Basin.

Ideally, the forces of nature should govern the Media Luna Watershed. But, this is not the case. Therefore, it is critical for us to band together, both political and scientific alliances, to preserve Media Luna as an environment where visitors feel safe, comfortable, and at home. Ultimately, we must learn to allow the watershed to live by its biological rules while allowing humans the opportunity to enjoy its many natural treasures.

During the many trips to the Rio Verde Watershed to gather information and photos for this book, I learned to admire the people of the region. Their friendship, kindness, and willingness to help me made this a terrific experience for a gringo from Texas.

Special thanks go to our wives, Sara and Erika. Sara provided unquestionable support during long periods while I was traveling to Rio Verde to collect information for this book. Erika kept us fed and made sure I always had a safe and comfortable place to stay. The authors are grateful to naturalist Fred Wills for his professional consultations and advice. I wish to acknowledge the encouragements and many excellent contributions of my friends. Dr. Jorge Palacio-Núñez’s guidance with fish identification and technical information was especially important and valuable. Seth Patterson’s professional ability to capture pictures of the fish in their natural habitat is greatly appreciated. The photos of the underwater world are from Seth unless otherwise noted. For outstanding photos taken by Seth during his visit to Media Luna check out: http://www.scubaboard.com/community/threads/trip-report-la-media-luna-san-luis-potosi-picture-heavy.502411/. Unless otherwise noted, the other photos were taken by me.

From Ossiel:

Having been born in Rio Verde, Media Luna is a unique location for me. It provides me a natural and positive energy. When scuba diving in Media Luna, you are surrounded by nature that permits one to reload and engage in the beauty. When I was a child, and I had to swim with my mother, I saw Media Luna as a vast expanse of water that is full of life. In addition to having a great time playing in Media Luna, I was always fearful yet curious about what lies beyond. Now, after many years, I still see Media Luna as a large body of water but with a particular sense of value and respect.

I met Richard and his wife, Sara, when they came to Media Luna to take a diving course. I was surprised by his interest in nature. As time went by, our perception and sensitivity for Media Luna grew little by little. Our interest in the site was growing, and we shared a special respect and admiration for the spring.

As I grew to love Media Luna, my need to know its nature intensified. To love such a fragile place requires one to know it. But to know it requires sensitivity and patience to study it and respect it. Overall, it needs a particular respect for nature to write about it.

Every day, I relive my first experience of wonder and excitement while swimming and diving here as a child as I teach my students the excitement of breathing underwater in Media Luna. I see a transformation of each of my students after diving in Media Luna as they change and develop a new view of nature.

Our society’s demands for travel is growing each year, and Media Luna does not escape this pressure. Every year the park is visited by more and more people, especially on weekends and holidays. Each time the use and abuse of the park grows. The impacts on the fragile shores of mud and dirt increase as people walk along the shores or get in and out of the water. The aquatic plants are destroyed, and many of the plants are covered with silt that settles on the leaves, preventing light from reaching them. The popularity of Media Luna has its daily price as more use means more time needed for recovery. Not long ago, recovery time after Holy Week was only a few days, now it takes months. The human impact is that much greater.

Richard has written this book at the right time with the goal to take action for a substantial and permanent change. I have been teaching diving and conservation at Media Luna for 23 years and have confidence that learning about the environmental impacts on Media Luna has high value. Man must find a balance between preservation and use of Media Luna to preserve it for future generations. Hopefully, through this work, we will learn to see Media Luna with sensitive eyes and respect for living things both in and out of the water, including man himself.

Chapter 1

INTRODUCTION

Any fool can know. The point is to understand.

Albert Einstein

A watershed is the area of land that drains rain or spring water into one location such as a stream, lake, pond, marsh, or wetland. They are some of the most productive and fascinating ecosystems in North America. Watersheds provide diverse ecological benefits including water purification, recreation, irrigation, and habitat for plants and wildlife. Unfortunately, the amounts of watersheds around the world are becoming more and more threatened. Used by man and animals since prehistoric times, the Media Luna Watershed has withstood human development, but today it may be at risk. The author and dedicated individuals have recognized the need for educating the community about protecting the remaining watershed surroundings in-and-around the Media Luna area. Through education, we can work to increase the understanding of the Media Luna Watershed and foster appreciation for its natural beauty. These pages will facilitate a sharing of ecological relationships and ideas usable in many educational settings. Specifically, this material should prove useful in teaching watershed ecology, environmental sciences, aquatic flora and fauna identification, and earth science aimed at the Media Luna Watershed.

Watersheds are vulnerable to loss or inadvertent destruction related to land development, agriculture, and recreation. These water bodies provide water for drinking, agriculture, manufacturing, recreation, and habitat for numerous plants and animals. Only by knowing the Media Luna Watershed and its ecosystem can we begin to understand why and where small changes can have enormous impacts.

Included is a guide to the identification of the fishes, plants, and other critters that depend on the watershed. We will briefly cover the changing uses of Media Luna and the management system that is in place. We conclude with a discussion of the environmental impacts of Media Luna.

The discussions will cover the entire Media Luna Watershed although when the name, Media Luna is used by itself, we are only talking about the spring lake. Also, when we speak of the canals and channels; canals will mean man-made waterways while channels will be natural waterways.

This book is a simple guide for those interested in learning more about the natural history of the Media Luna Watershed. It is not all-inclusive of the aquatic plants and birds seen around the watershed. The objective is to identify the most common aquatic plants and birds that depend on the watershed. The chapter on the fishes of the Media Luna Watershed is current. The overall goal is to provide a learning tool for the new or amateur naturalist or biologist, as well as any person with a curiosity about what life exists within the watershed. We have incorporated Laguna Los Peroles and A la Ateojitos into the territory covered because of their biological and geologic links to Media Luna.

Los Anteojitos is a smaller aquatic habitat with two modest lagoons connected by a small channel. Los Anteojitos is only 6 km from Media Luna and believed to have subterranean connections. The overexploited Los Anteojitos is now seldom used by tourists.

Los Peroles is another aquatic habitat with possible subterranean connections. It is smaller but similar to Media Luna. Some people call it, Little Media Luna.