Vol. 22, Issue 12, April 26, 2006
Jose G. Peña
Driest Winter-Spring on Record; Start Planning to Survive the Drought
April is rapidly coming to a close, tied with April 1920, as the 2nd driest April on record with only about 0.06 of an inch of total rainfall. In addition, the mid-October-2005-to-date period is the driest period on record with only about 1.5 inches of rain compared to a long term average of close to nine inches for the same period. The moisture situation is completely different than a year ago at this time. A year ago, the soil profile was full of moisture from significantly above average winter/spring ‘05 rainfall. Cumulative rainfall remained over 100 percent of the long term average by the end of April ‘05. Now, cumulative January ‘05 through April 25, 2006 rainfall, (when this report was prepared) is about 59 percent of the long term average. (See Figure 1). In addition, unseasonably warm weather during the past two weeks with afternoon temperatures averaging about 10°F above the typical average for this time of the year are aggravating the dry spell.
The drought really started in June ‘05 when cumulative rainfall dropped to 73 percent of the long term average. Weathermen define a true drought as a period when 75% or less of the long term average yearly rainfall has been received. The Southwest Texas region certainly qualifies as under a drought. And, weather forecasts indicate that the drought will persist in the South Central portion of the U.S. through the summer. We should carefully and seriously plan how to survive this drought.
It has been said that Texas is the land of perpetual drought, with occasional floods. This statement appears to have the basis of fact when we review rainfall patterns in 1996, 1998, 1999, 2000, 2002, 2003, 2006 and the floods of 1997 and near floods during July-October ‘02. Texas is enduring a seventh drought in eight years.
The dry weather has forced ranchers to liquidate all or part of their herds and/or provide heavy supplemental nutrition. Hay is scarce and expensive. Crop agriculture is experiencing increased irrigation requirements at a critical time of record high energy costs.
If, for planning, we only consider rainfall since November ‘05, drought planning calls for drastic measures. Figure 2 provides a summary of the moisture situation from November ‘05 through April 25, 2006. We are entering the critical spring production period with only about 17.5 percent of the normal long term cumulative rainfall. Spring normally accounts for about 70 percent of the annual production.
While the market for calves, feeders and lambs remains very attractive and some may want to retain their livestock, this dry spell may require further stocking adjustments. Wildlife resource use is rapidly becoming the economic viability of ranching industry in Southwest Texas. A drought management plan should prioritize wildlife management, to the extend that it is economically feasible. Further reducing livestock stocking rates may help protect remaining wildlife since both complete for the same resources. Under conditions of feed shortage, livestock feed more heavily an browse which normally sustains deer throughout the year. Cattle will also graze down bunch grasses that provide vital resting habitat for quail. Reducing livestock stocking rates before they begin to compete seriously with wildlife is essential if valuable game species are to survive the drought and remain a valuable commodity, i.e., good set of antlers and plump quail.
Water is no doubt the most important of all nutrients for all living things, but especially for wildlife and livestock. Since ruminants, such as cattle and deer, are able to store large amounts of water in their stomachs, they are better adapted in surviving droughts than monogastrics, such as hogs. The absence of drinking water may force a livestock liquidation decision. Wildlife are more mobile and will travel great distances to water. When movement is restricted by high fences, however, special water arrangements should be considered to protect wildlife.