Saturday, April 6, 2019

Borrego Valley Hawkwatch-Post Season Highlights-Thursday April 4-Sunday April 7, 2019

The season has been completed, however the hawks continue. A few days after we officially finished the season, we discovered a huge congregation of hawks in the old potato fields to the east and also east of the airport . As anticipated, hawks that had been feeding in Mexico and locations other than Borrego Springs began entering the valley. On Thursday and Friday April 4 and 5, over a 1,000 Swainson's Hawks were observed at several locations. Today, Saturday April 6, we witnessed around 500 hawks mainly from the airport location. The wind at the Henderson Canyon Rd site was raging at 30-40mph. Although we are not counting hawks as they migrate, we are continuing to alert the public. It's still a thrill to observe hundreds of hawks kettling and feeding. Check out the youtube from Friday April 6th near the airport. https://youtu.be/qp40E4YUNBY

Just got word (5:30pm Saturday April 6) that around 100 hawks dropped into the dunes at Old Springs Road-road to the dump off of S-22 where it turns north. This is the Old Springs County Preserve as you drive onto Old Springs Rd.

Sunday April 7, a day to remember. We checked out the county preserve and found a half dozen hawks on creosote bushes. I then went to the hill south of Henderson Canyon. We will have to name this hill as it provides a great overview of potential roosting and feeding sites. I spotted over 100 hawks on the ground and another 150 kettling up. As I scanned to the east I picked up an additional 50-75 hawks in a kettle. Hawks began to rise and stream all around me. All of the hawks eventually moved to the north and west, streaming out of the valley. I had at least 8 separate kettles of hawks at one time after the initial departure. I believe the total count was around 500+ hawks.

Monday April 8, I thought it was over! Well over 300 hawks migrated today. The best viewing was on Henderson Canyon Rd. I've decided to name the hill south of Henderson Canyon Rd "Lily Hill". There are several Desert Lily Plants on the Hill.
Desert Lilies at Lily Hil

Our first photo is of Andy, our greeter at the evening watch. In this photo he is vocalizing. The life span of an Anna's Hummingbird is 8.5 years. Andy is at least 8 years old. All the hawk shots were taken April 5-6. All of the hawks below are Swainson's Hawks. Named for Swainson's a 19th century naturalist by Lucian Bonaparte (nephew of Napoleon) based on a painting by John James Audubon that was created by a specimen caught by Townsend. A remarkable combination of famous naturalists and artists.



Our Official Greeter At The Evening Watch-HC


Adult Rufous Morph SW-Dave Clark

Adult Light Morph SW-Dave Clark
Nice Kettle of Swainson's Hawks-Aedyn Loefke

Adult Female Morph SW-Tom Hamilton

Adult Light Morph SW-Tom Hamilton
Adult Dark Rufous SW-Frimmel Smith

Adult Light Morph SW-Frimmel Smith

Sub-Adult SW-Frimmel Smith

Sub-adult Dark Morph SW-Frimmel Smith
Light Morph SW Taken With I-phone-Dana/Megan Draper

Light Morph SW-Frimmel Smith
Subadult Light Intermediate SW-Ted Spriggs Jr. 
Canadian Paratroppers Passing a Swainson's Hawk-HC
Adult Light Intermediate morph SW-Kwan Choo

Adult Male Light Morph SW-Kwan Choo


Adult Male Light Morph SW-Kwan Choo

Dark Morph SW-Kwan Choo

Monday, April 1, 2019

March 30-March 31, 2019-Finally A Day With a Decent Migration

Leaders: March 28, 29, 30, 31
Rose
Hal

Migration:
March 28-Swainson's Hawks-2
March 29-0
March 30 Swainson's Hawks-371; Turkey Vultures-6
March 31-57 Swainson's Hawks

Discussion:
After a virtual hawk drought, we had a wonderful evening event March 29. We counted 511 Swainson's Hawks dropping into the date farm. On March 30th we counted 371 Swainson's Hawks migrating and around 100 going east to feed. March 31st, our last official count day yielded an additional 57 Swainson's Hawks. We did see some hawks (around 17) the evening of March 31st. I received a message of about 100 hawks feeding in fields to the east as well. We will continue to monitor the evening watch but will not record migration.

This season did not produce many highlights. The average seasonal totals for 17 years-Swainson's Hawks is 4,523. Our total Swainson's Hawk count for 2019 is 1,086. THIS IS NOT AN APRIL FOOLS JOKE. This is the lowest count we have ever had.

The question of "why are the number of hawks down this season, with all the food available". It's because of the abundance of food throughout Southern California and Northern Mexico that our hawk numbers are down. The hawks have spread out throughout the region and don't need to come to Borrego Valley to feed. Perhaps after the caterpillars have diminished in numbers, the hawks will migrate through the valley. It would have to happen within the next week as the hawks will have gone north one way or another.

The caterpillars (see below) come in several color morphs. The question remains, why different morphs?

Light Morph Swainson's Hawk-Randy Lenon

Light Intermediate Morph Swainson's Hawk-Randy Lenon


Light Morph Eating An Ant? Randy Lenon

Small Kettle-Randy Lenon

Possible Sphinx Moth Egg-Little Surprise Canyon-Randy Lenon

Tiny Caterpillar in the Background-First Instar-HC

Dark White-lined Sphinx Caterpillars-Randy Lenon


Green White-lined Sphinx Moth Caterpillar-Ted Spriggs Jr. 


Yellow White-lined Sphinx Moth Caterpillar-Ted Spriggs Jr.