Rich,
I have been spending a fair amount of time on the western part of the West Unit of the Pawnee Grasslands this summer tracking the activities of loggerhead shrikes. I have seen virtually no Swainson's Hawks. I recorded a whopping 1 on each of two 150-mile loops in the last month. Grasshopper expert Tim McNary, formerly of USDA-APHIS and now an affiliate of the Gillette Museum at Colorado State recently went out to Crow Valley and came home with only a dozen or so specimens of hoppers of, I think, four species! Tim can usually find that many before he gets out of the car! Normally the most commonly impaled object of shrikes are grasshoppers (particularly two species, Xanthippus corallipes and Arphia conspersa). This summer, I've maybe seen a total of 10 grasshoppers impaled. I've seen 5X that many hoppers impaled in one shrike territory in years past. Very few big hoppers this year on the northern prairie. The shrikes have compensated by terrorizing herps and various crickets.
I have heard the hopper population in southeastern CO is just the opposite, at least at present in terms of nymphs. Clouds of them when you walk thru a pasture. Maybe there are also good hopper populations in the meadows of the Wet Mountains. All the moisture is growing green hopper food, i.e. plants. Maybe what you saw is a regional relocation of hawks in response to food abundance, sort of like what we're seeing with dickcissels. Maybe many of the hawks that normally populate the northern plains never made it up here, or maybe had second thoughts once they got here and drifted back south, who knows? I do know I had that big number of 160+ Swainson's hawks on my Lamar BBS route which was bizarre in my experience. I received comments that these were probably mostly young, non-breeding birds that just come north to loaf and feed for their first independent summer before returning south. Maybe the majority of what you saw was this age group. My bet would be the majority of buteos were Swainson's, and that they were also somewhat staging for their later departure south.
Interesting, whatever it was. Thanks for your post.
Dave Leatherman
Fort Collins
--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+unsubscribe@googlegroups.com.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+unsubscribe@googlegroups.com.
To post to this group, send email to cob...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/154697.77ba384a.46aecff5%40aol.com.
For more options, visit https://groups.google.com/d/optout.
--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/SN1PR0601MB16158700AF58DA591CFDD00CC1BD0%40SN1PR0601MB1615.namprd06.prod.outlook.com.
Dan et al.,
That is the large Plains Lubber (Brachystola magna) which comes in two color forms. Flightless, they are most abundant in areas with poor soil or in weedy areas adjacent to fields or roadways. Males are 40 mm long and females 50-60 mm. They will feed on insect cadavers but specialize on ragweed, sunflowers and other broadleaved plants.
I am leading a grasshopper walk at Chico Basin Ranch for Mile High Bug Club next Saturday, 4 August. We should see 35-40 grasshopper species if you or any birders are interested.
Bill Maynard
Colorado Springs
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+u...@googlegroups.com.
To post to this group, send email to cob...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/154697.77ba384a.46aecff5%40aol.com.
For more options, visit https://groups.google.com/d/optout.
--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+u...@googlegroups.com.
To post to this group, send email to cob...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/SN1PR0601MB16158700AF58DA591CFDD00CC1BD0%40SN1PR0601MB1615.namprd06.prod.outlook.com.
For more options, visit https://groups.google.com/d/optout.
--
Cheers,
Dan Maynard
Denver, CO
--
You received this message because you are subscribed to the Google Groups "Colorado Birds" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cobirds+u...@googlegroups.com.
To post to this group, send email to cob...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/CAN0ycWi6fcWoQX5Xg3y%2Baewr70AvBnBP4pLP1GACybF6aF72XA%40mail.gmail.com.