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

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.

Closing In On The Lowest Count In 17 Years In A Remarkable Flower/Caterpillar Season

Leaders:March 21-March 28, 2019
Don White
Hal Cohen
Herb Stone
Laura Webb
Pam Albers
Rose Leong

Migration:
March 21-0
March 22-12 Swainson's Hawks
March 23-3 Swainson's Hawks
March 24-0
March 25-11 Swainson's Hawks
March 26-14 Swainson's Hawks; 10 Turkey Vultures
March 27-1 SW; 6 TV's
March 28-2 SW's

Discussion:
Since my last post we have had a total of 43 migrating Swainson's Hawks and 16 Turkey Vultures. This period of time traditionally yields thousands of migrants. This season we have had a remarkable flower bloom along with widespread caterpillars. The White-lined Sphinx Moth caterpillars can be found across several hundred square miles in Southern California and Northern Mexico. The Swainson's Hawks have most likely spread out to feed on the caterpillars. We should be grateful that the health of the hawks is probably pretty good with such an ample food source available.

Our evening watch has not been very exciting. Although occasionally we see a burst of activity to the east. A few nice kettles of hawks has been observed. Unfortunately the migrating hawks have moved much further away from the morning watch site. Will the hawks finally move through Borrego Valley after the caterpillar numbers dwindle? So far the number of caterpillars seems to be increasing and spreading throughout the region. Do not make the mistake of confusing the sphinx moth caterpillars with the huge number of Painted Lady Butterflies. Over 1 billion Painted Lady Butterflies have migrated through Southern California. The plant selection of the butterflies is different than that of the sphinx moths. The Swainson's Hawks evidently do not feed on the butterfly caterpillars as they are heavily armed with bristles and may not be appetizing.

Speaking of appetizing, a few hardy raptor watchers have finally participated in a traditional ritual that was very popular for hundreds of years by the native Cuhuilla Indians. Below is a narrative written by William Greenwood Wright in 1884.

“In an hour we came to the caterpillar pasture. The sand is dotted with mats and patches of a procumbent plant, much resembling in flower the common sand verbena, Abronia, on which vast armies of caterpillars are feeding; they are huge worms three and four inches long. Another small army of Indians—[men, women, and children]— are out gathering them as though they were huckleberries, for use as food. The Indians do not notice us, but go on with their gathering. Seizing a fat worm, they put off its head, and by a dexterous jerk the viscera are ejected, and the wriggling carcass is put into a small basket or bag, or strung upon strings and hung upon the arm or about the neck, till occasion is found to put them into a large receptacle.1 got three of these gathering baskets. One is funnel-shaped, holding a quart or two; another is like a large, flat saucer, and the third is similar but with a deep rim. At night, these Indians carry their prey home, where they have a great feast. Indians from a long distance come to these worm feasts, and it is a time of great rejoicing among them. The larvae that are not consumed at the time (and they eat incredible quantities), are put upon ground previously heated by a fire, and thoroughly dried, when they are packed away whole, or pulverized into a meal [Wright 1884:283].” 

We tried to perform the same ritual and found the worms to be very tasty. If I were served this delicacy in a restaurant, I would order more. 

Robin Roberts-White-lined Sphinx Moth Showing Proboscis

Sphinx Moth Caterpillar-Randy Lenon

Sphinx Moth Caterpillars Crowded Together-Randy Lenon

Sphinx Moth Caterpillars Cleaned, Broiled and Ready to Eat-HC

Painted Lady Chrysalis-HC

Painted Lady Butterfly-HC

Slow Season Thus Far-Very Slow Compared to the Previous 16 Years

Leaders: February 25-March 20:
Hal Cohen
Judy Davis
Rose Leong
Herb Stone
Laura Webb

Migration:
February 25-March 20: 607 Swainson's Hawks; 34 Turkey Vultures

Discussion:
Southern California is experiencing a remarkable flower bloom. With the exceptional bloom we are witnessing a White-lined Sphinx Moth caterpillar explosion. Because caterpillars are found in numerous locations, Swainson's Hawks have ample opportunities to feed during the northward migration. Borrego Valley is only one small area for hawks to feed in. I believe that the radically low numbers of SW's is a result of widespread feeding and not a diminished Swainson's Hawk population. To date (March 20), we have counted only 607 Swainson's Hawks from February 25 to March 20th. The total count for 2019 is 615 Swainson's Hawks. Traditionally by this period we should have counted a few thousand SW's. Regardless of the low numbers we have had some great views on occasion. Below are some photo's and movies. Check out the youtube of March 18. https://youtu.be/JRLgckvtcLQ

Ocotillo Wells-HC

                                           Blow Sands Area Near Borrego Springs-HC

5 Swainson's in Eucalyptus Tree-Borrego Valley Rd. David Nevett

Leaving the Roost-David Nevett

Rufous Morph Swainson's Hawk-William Carter

Subadult Intermidiate (Rufous) Morph SW's-Krisztina Scheeff

White-tailed Kite-Krisztina Scheeff

Begin a New Season-2019-Possible Super Bloom Again

Leader:

February 21-Judy Smith

February 22-Laura Webb

February 23-Hal Cohen
February 24-Herb Stone

Migration:
February 21-1 Turkey Vulture
February 22-8 Turkey Vultures; 1 Swainson's Hawk
February 23-33 Turkey Vultures; 2 Swainson's Hawks
February 24-13 Turkey Vultures: 5 Swainson's Hawks

Discussion:
It has been a very cold rainy winter season. We've had over 7 inches of rain over a period of weeks. There are numerous flower hot spots surrounding Borrego Springs. With the warmup beginning Sunday February 24 we could experience another super bloom, lots of caterpillars and thousands of hawks. So far only a handful of hawks has migrated through the valley. However it looks like more Turkey Vultures are venturing into the valley.

Evening Watch:
No hawks and one TV were evident this evening (Feb 24th). There are TV's roosting in the usual spot in the Roadrunner

Early February Flowers Along Near Arroyo Salada-S22-HC

Entering Borrego Springs From Ranchita-February 23, 2019