FOOTPRINTS IN THE DESERT SAND TELL A TALE OF DESTRUCTION

Jayne Belnap left behind her footprints in the desert 8 years ago and when she returned with specialist Dave Evans they were still there.  Just walking across the desert damaged the soil’s ability to support life so much that it hadn’t recovered.  “The biological soil crusts are so fragile that when they are destroyed it takes decades and decades for them to recover,” says Evans. 

The desert floor may look barren, but the surface teems with life ranging from lichens to algae to tiny critters. That life depends on the richness of the soil, which in turn depends on the amount of nitrogen the soil contains.  When Belnap and Evans analyzed the soil beneath her old footprints, they found that nitrogen had been seriously depleted. The amount of nitrogen depends largely on the plant growth within the upper soil, and it only took one footprint to kill so much of the fragile system that the nitrogen level plunged. 

“It takes a long time for the desert to heal itself,” says Jeffrey Klopatek, professor of plant biology at Arizona State University in Tempe and an expert on desert ecology. “In many cases, it never will.” 

---Source ABC News, Science, Lee Dye reporting---

THE NORTHERN RIGHT WHALE IS A SPECIES IN GRAVE PERIL

The North Atlantic northern right whale is headed for extinction unless human intervention improves survival, according to a study published Wednesday (March 17, 1999) in the “Proceedings of the National Academy of Sciences.”

Several thousand right whales once existed in the North Atlantic Ocean, but commercial hunting at the turn of the century severely depleted whale populations. For the past 60 years, the species has been protected.  However, despite conservation techniques, right whale populations have never recovered. Their numbers are currently estimated at about 300.

Since 1980 their survival has declined dramatically and population growth rate has gone from positive to negative.  Under current conditions, the population is headed for extinction in less than 200 years, the study shows.  The population seems to be recovering more slowly than other whale species, such as humpbacks. Why this is happening has not been documented.

Most right whales are killed by collisions with ships, according to the National Oceanic and Atmospheric Administration. Slow moving in general, the whales are especially slow when accompanied by calves. With only the flat of their back visible at the surface, they are difficult to detect from large, fast moving vessels. 

NOAA is at work to teach ship operators how to recognize and avoid right whales, and fishing grounds have been closed during certain periods in some areas frequented by the whales, such as Cape Cod Bay and Great South Channel.”

---Source - Environmental Network News---