PHOENIX — The significant fish die-off last week on the Verde River below Horseshoe Dam was the result of a lack of oxygen, and not because of anything found in the river, according to a water-quality investigation compiled by the Arizona Game and Fish Department.

On Thursday and Friday, the Department collected water-quality samples, analyzing fish for bacteria, viruses and parasites. The fish die-off was in an area approximately 100 yards downstream from Horseshoe Dam, which is operated and managed by Salt River Project for the Bureau of Reclamation.

It is estimated that approximately 20,000 fish were killed. About 60 to 70 percent were goldfish and carp. The remaining fish species were comprised of largemouth bass, flathead catfish, channel catfish, and bluegill. The Department believes that most of the fish killed were from Horseshoe Lake and that only a small fraction may have been from the Verde River below Horseshoe Dam.

On June 1, SRP began releasing approximately 1,000 cubic feet of water per second from Horseshoe Lake. SRP empties Horseshoe Lake each year to comply with the Horseshoe-Bartlett Habitat Conservation Plan (H-BHCP), which was established with the U.S. Fish and Wildlife Service under the authority of the Endangered Species Act (ESA) to protect endangered species from potential impacts of SRP’s operation of Bartlett and Horseshoe dams.

Mitigation activities in the H-BHCP, including the annual rapid draw-down of Horseshoe Lake, were developed to benefit native birds, native fish and reptiles in the upper Verde River that are listed as threatened or endangered under the ESA. Specifically, the draw-down of the reservoir increases riparian nesting habitat availability for the southwestern willow flycatcher and yellow-billed cuckoo, while decreasing the numbers of non-native fish species that may compete with, or prey upon, native fish in the upper Verde River.

By June 28, the reservoir was nearly empty. As the reservoir level decreased, the fish in Horseshoe were concentrated in an increasingly smaller area. Sediment that was disturbed as the water was being drawn down consumed dissolved oxygen, resulting the low oxygen levels and causing the die-off.

As the last of the water was released from Horseshoe, the dead and dying fish were passed through the dam into the Verde River. Some of these fish may eventually drift down to Bartlett Lake.

In the meantime, it is important for anglers to remember they should not be taking these dead or dying fish.

PHOENIX — You can fish Arizona waters for free this Saturday, making this an ideal time to take the family out for some fun and relaxing outdoor recreation.

Arizona’s Free Fishing Day will be celebrated on June 4 this year as part of National Fishing and Boating Week, which runs June 4-12. This Saturday, no fishing licenses are required for persons fishing any public waters in Arizona.

“Whether you’re an experienced angler who wants to introduce a newcomer to the sport, or someone who’s always been interested but never took that next step, this is an ideal time to gather up some friends and family members and head out to your nearest community lake, or head up to the cooler country to fish a lake or stream,” said Nick Walter, editor of the Arizona Game and Fish Department’s Weekly Fishing Report.

Remember that bag limits and other fishing regulations are in full effect and must be observed on Free Fishing Days. Kids under the age of 10 can fish for free all year long in Arizona, so this special fishing license exemption day means that the older kids and parents get a free pass for the day.

The Arizona Game and Fish Department will also sponsor some free fishing day clinics/events to give people the opportunity to try out this fun, family-oriented pastime. Loaner fishing rods, bait and instruction are provided for free at most of these venues.

Times and locations of the events are:

Saturday, June 4:

• Lake Pleasant Regional Park, 41835 N. Castle Hot Springs Rd., Morristown, 7-10 a.m.
• Goldwater Lake, 2900 S. Goldwater Lake Rd., Prescott, 9 a.m. 1- p.m. The Mora National Fish Hatchery in New Mexico will be providing retired Gila trout broodstock for the clinic, and there is potential to catch a world record Gila trout. The record is 3 pounds, 7 ounces caught by Bo Nelson from Frye Mesa Reservoir on March 19, 2011.
• Deadhorse Ranch State Park, Cottonwood, middle lagoon, 8 a.m.-noon. Entrance fees for participants are waived during this time period only. Channel catfish will be stocked prior to the event.
• Garrett Tank, approximately 12 miles east of Seligman off of Crookton Road, 9 a.m. to 3 p.m. Open to public. No signups.
• Dogtown Lake, 1250 Pine Top Dr., Williams, 9 a.m. – 1 p.m.

Saturday, June 11:

• Parker Canyon Lake, Elgin, 9 a.m. – 2 p.m. See more information.

PHOENIX — Your next outdoor adventure just got more affordable: through May 30, the Arizona Game and Fish Department is offering half-price discounts on short-term fishing licenses. The license discount is only available online.

This is the first time the Arizona Game and Fish Department (AZGFD) has offered such a license discount. AZGFD is excited to be able to offer better products and increased value while continuing to conserve wildlife for future generations.

Just in time for the Memorial Holiday weekend, short-term (one-day) fishing licenses are only $7.50 per day for Arizona residents and $10 per day for non-residents.

Pick your favorite spot, and get back to basics with some quiet time at the lake. This is the perfect opportunity to tussle with some tiger trout that will be stocked into Mogollon Rim lakes just in time for the first big camping weekend of the year.

In spring 2013, Senate Bill 1223 gave the Arizona Game and Fish Commission authority to change license structure and fees through a streamlined, customer-focused process. AZGFD, which receives no general fund tax revenue, now has the flexibility to offer new products and pricing in response to changing conditions and customer needs.

Visit azgfd.gov for more information and to stay “in the know” on future offers and products.

In Williams, fishing licenses are available at the Outdoor Store on Fourth Street and Route 66, Saya’s on First Street and Route 66 and other locations.