After Finch's request for info on this species, thought I would copy and paste some info that Mitch Heindel, Kimball Garrett and Steve Sosensky have saved in a file in LACoBirds in case anyone else is interested. Although it sounds like Finch looked in the right area and didn't succeed. This seems to be the most requested species from visiting birders.
If anyone wants Yellow-chevroned Parakeet, I can definitey help you there - they wake me up at 7am every morning!
Where to Find Spotted Doves
from Mitch Heindel
Spotted Doves are very common in the PV/SoBay area still. Driving south on the 405 from LAX one usually starts to see them about Redondo Bch. Blvd. exit, which you can take a mile east to Alondra Pk. and probably see them. Most South Bay or PV Peninsula parks have them...
They are also at Banning Pk., Harbor Pk., Peck Pk. in San Pedro.... A dozen live around the intersection of Western Ave and Torrance Blvd. They like areas with large trees, but will accept sparsely treed residential areas too, particularly those with tall dense hedges. While they have declined somewhat here in the last decade, they remain "common".
I believe the declines are related to the recolonization of breeding Cooper's Hawks. Spotted Dove is the most common pile of feathers found in our city parks. One pile today at Banning was SPDO. Spotted Doves expoloded in a period when Coops were absent as nesters locally. Now with their return of the last decade, SPDO is the primary food source.
from Kimball Garrett
They are still common in western Long Beach (e.g. along Ocean Dr. east of the end of the 710), but have declined greatly or vanished from much of eastern Long Beach (and essentially all of Orange County).
Some visitors are restricted to an hour or so around LAX. Although Spotted Doves are still to be found in the residential areas around the airport (Westchester/Inglewood/El Segundo), they're not the instantaneous slam-dunk they used to be. Nevertheless, with a little bit of driving around, birders should have no trouble finding them in this area. They're also in the residential areas east of the Harbor Freeway (e.g. Compton north to Huntington Park), and they are holding on in the southwesternmost part of the San Gabriel Valley (e.g. Alhambra).
Spotted Doves remain fairly common in parts of the central L. A. Basin; one spot I recommend is Echo Park, just NW of downtown Los Angeles. (Easy to find daily, though fewer than in past years).
As for the causes of the striking decline in this species, I agree with Mitch that it likely has something to do with urban predators. Cooper's Hawks (which, amazingly, were a blue-listed species of concern not too many years back) are common urban breeders now. But we can't ignore the phenomenal boom in American Crow (and Common Raven) numbers in urban areas and their impact as nest predators. I suspect that proliferating Eastern Fox Squirrels are also a factor, though Spotted Doves have declined in some areas where these squirrels are still scarce or absent. Why haven't these predators wiped out Mourning Doves as well? Here, I think it may be the much narrower ecological range of Spotted Doves -- they're pretty limited in their nest sites (medium heights in large shrubs or trees) whereas Mourning Doves will nest just about anywhere and everywhere. Finally, we should at least consider the possibility of disease as a cause in Spotted Doves decline, though there is no concrete evidence of this.
One thing that is certain is that the decline of Spotted Doves cannot be attributed to the establishment of Eurasian Collared-Doves (unless they've committed suicide in anticipation of the invasion). The decline of Spotted Doves in Ventura County began before ECDs boomed, and over much of southern California (including L. A. County) the loss of Spotted Doves has occurred in places that still lack ECD populations .