SCR MAPS


South Concho River MAPS Station
2013
The spring migration season provided better than average numbers of most expected species and several interesting records of birds not often banded in the Concho Valley. Given the excellent breeding season in 2012 and the good migration season, we entered the 2013 MAPS Season with expectations of a good year.  The first session on May 11 resulted in good numbers and good species counts of breeding birds along the South Concho River. That was followed by three sessions with  lower than average numbers of birds and species at the station.  When we reached the middle of June without a major influx of hatching year birds, we became concerned about the breeding success of the birds breed in our station area.  Our fears were relieved in late June and early July when record numbers of hatching year birds emerged all over the MAPS Station area. We replaced the lower than average numbers recorded early in the season with two record sessions in a row during this time. The total breeding success of birds along the South Concho River seems assured as this year's MAPS season starts drawing a close. Although several interesting records associated with our 2013 MAPS season have emerged, none proves more interesting or unusual than the recapture of an adult male Cooper's Hawk that was originally netted in June of 2011 and recaptured in that same net in late May of 2013.

2011 and 2012
The first season for the South Concho River MAPS Station took place during the height of a historic drought was described as the worst in more than one hundred years. We entered that season expecting our production at the station to be greatly reduced by the drought. Nothing could have been further from the truth. We started that season by handling 60 birds during the first session and this trend continued for most of the breeding season.  We completed the season with 320 birds and forty species. Fourteen of these species were migrants and twelve were transient birds that most likely did not breed at the station.  During this season we banded and recaptured far fewer hatching year birds than expected.  For example, Painted Buntings and Lark Sparrows breed here in good numbers during a normal season. These species were present for most of the season but the majority of both species abruptly left the MAPS area shortly after the middle of July and very few hatching year birds were banded of these two species.  The large number of transient and migrant species recorded at the station was likely influenced by the lack of reliable water sources away from the spring fed river. The first season many question unresolved in our minds.

 During the winter and early spring of 2012, good rains covered most of this region and the second season opened with conditions much different than 2011. Plants that did not germinate in 2011 covered the entire MAPS circle in great profusion. Under these lush conditions, things seemed right for a good  breeding season.

The very limited breeding success for most birds during the 2011 drought conditions was confirmed during our spring migrant banding. We banded far fewer migrant birds, fewer returning summer residents and fewer species than we had banded in previous years. Permanent resident birds were also present in reduced numbers throughout the spring. The first MAPS session reflected these trends. When compared to the first session of 2011, we banded far fewer migrant birds and encountered limited numbers of resident birds.  These trends have continued throughout the first four sessions of our survey. We are currently encountering about half as many birds as last season and species numbers are also reduced.  It seems obvious that the large numbers from last season resulted when many more birds were forced into the river corridor for water and other resources.  Resources of all kinds are more available during this season and there is no concentration of birds in the river corridor. With numbers of resident birds reduced by the lack of breeding success in 2011, the data from this season would seem to support our original reasoning for our results from last season and our predicted results for this season.

These changed conditions have also affected results from individual nets. Last season, our most productive nets were in areas where resources were concentrated. This season with more available resources, these nets are not producing the same percentage of birds as last season. Other nets that had limited production last season are now producing above average results.  A large patch of Nodding Thistle near one net has resulted in encounters with several thistle feeding birds that were not recorded at this net last season. With these trends established, we anticipate a more normal year at the South Concho River MAPS Station but conditions could change as the summer progresses and resources become more limited.

Although overall numbers are reduced, we are encountering good numbers of juvenile birds in all locations and have reason to believe that we will have a good breeding season for the birds that are present in the station circle. The summary for the 2012 MAPS station can be viewed by clicking the link below.