Zion National Park's natural resources are being strained by development of inholdings and properties surrounding the park, its air quality is impaired by pollutants, and overcrowding is impacting the visitor experience, according to a "State of the Park" report issued this week.

According to the 79-page report, the park's ecosystem processes are suffering most greatly from development, both in and outside of the park. "The park is concerned with the ecosystem being able to function within the natural range of variability," the authors wrote.

Record visitation also is a concern of park managers, as the report pointed out that, "increasing visitation has led to concerns among park managers about overcrowding, infrastructure limitations, and resource protection. Increasing visitation also affects the availability of recreational opportunities for visitors."

The park is rapidly becoming a year-round destination with an ever-shrinking slow season in December and January. The past five year trend in visitation from 2010–2014 has shown a 19.37% increase. Increased visitor density accelerates wear and diminishes facility lifecycles. The park now routinely receives negative comments about crowding. The number of resource impacts monitored by staff such as campsite sprawl, human waste, additional canyoneering anchors, illegal campfire scars, and braided or multiple trails have greatly increased in recent years. Aggressive wildlife behaviors toward humans by deer and squirrels have been observed at popular, crowded park destinations, presumably due to feeding animals and their acclimation.

With those growing crowds come growing amounts of wastes, both from purchases as well as from humans, as this sidebar notes:

With rising real estate prices, the National Park Service's "ability to purchase inholdings is decreasing..."

Beyond real estate prices, the park's budget itself has not kept up with demands on park staff and resource issues.

Base budget increases for park operations have not kept pace with the demands on staff associated with increased visitation. The shortage in operational budget and staff level for what is becoming a year-round park is being felt in every division. ZION relies heavily on seasonal staff, limited to 6-month appointments. This requires the inefficient and costly practice of recruiting, hiring, and training two sets of seasonal workers each year to cover these expanded operations. This places a multiplied workload on supervisors and the Servicing Human Resources Office (SHRO) staff. This need to hire multiple sets of seasonal workers is felt throughout all aspects of park operations, including law enforcement and emergency response; maintenance of roads, trails, grounds, buildings and utilities; fee operations, and visitor information and education services. Budget and staff shortages also adversely affect the knowledge base and management of the resources for which the park was established and that visitors come to enjoy. There is also no funding for most data needs identified in the park foundation document.

Other areas of concern cited by the report included "Cultural Anthropology," where there's a need for an"ethnographic overview and assessment study" to be completed "to document baseline cultural anthropology data for the full spectrum of park resources and traditionally associated tribes and communities." Too, more research is needed into the historic structures found in the park, the report said.

Air quality is a concern, too, as vistas at times are obscured by pollution, ozone levels sometimes rise above acceptable levels, and airborne heavy metals (e.g., mercury) are impacting the natural resources, as a "recent study found elevated mercury levels in small prey fish."

Light pollution from nearby towns is increasingly impacting Zion's night skies, the report said.

Despite those areas, there are many other aspects of the park that are in good condition. The 144 miles of Wild and Scenic River sections in the park seem to be in good condition and stable, native wildlife populations seem to be stable in both number and distribution, and non-native species are low and not of concern.

The park's carbon footprint also is shrinking, according to the report.

Zion is recognized worldwide for its sustainability efforts. Highlights include: the propane-powered shuttle fleet which eliminates thousands of private automobiles from driving in the park every day, highly efficient buildings, water bottle filling stations to reduce waste (the first in the NPS), photovoltaic panels which provide ≈12% of the park’s electricity needs, electric and alternative fuel vehicles, a park composting program, and an extensive recycling program for residents and visitors.

And while Zion experienced record crowds in recent years, overall, 99 percent of park visitors during fiscal 2014 reported a satisfactory stay in the park. Both "Wilderness Character" and "Wilderness Stewardship" in the park were considered to be in good shape. "The amount of trammeling actions authorized by the NPS, NPS structures in wilderness, livestock trespass, and motorized equipment use have all dropped in recent years," the report said. "Visitor demand for recreational use of the wilderness continues to rise even though use levels through much of the wilderness are limited through a permit system."

This report is extremely deep in information pertaining to the park resources, from geomorphology and the richness of plant communities (though pinyon-juniper stands are in danger) to the recovery of the California condor in the park and problems by the park staff to manage natural wildfires that benefit ecosystems in the park.

You can find the entire report online here.