US Bird Conservation Regions

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1 US Bird Conservation Regions Completion of Requested Changes ( ) Produced for U.S. NABCI 10 July 2012 Updated December 2012 Eva Jenkins Andrew Couturier Bird Studies Canada / Études D Oiseaux Canada P.O. Box/B.P. 160, 115 Front St., Port Rowan, ON Canada N0E 1M0

2 EXECUTIVE SUMMARY About Bird Conservation Regions Bird Conservation Regions (BCRs) are ecologically distinct regions in North America with similar bird communities, habitats, and resource management issues. They are based on the scale-flexible hierarchical framework of nested ecological units delineated by the Commission for Environmental Cooperation (CEC). These ecoregions encompass areas that are similar in their biotic (e.g., plant and wildlife) and abiotic (e.g., soils, drainage patterns, temperature, and annual precipitation) characteristics. BCRs may be partitioned into smaller ecological units when finer scale conservation planning, implementation, and evaluation are necessary. Conversely, BCRs may be aggregated to facilitate conservation partnerships throughout the annual range of a group of species, recognizing that migratory species may use multiple BCRs throughout their annual life cycle. BCRs also facilitate domestic and international cooperation in bird conservation because these areas of relatively homogenous habitats and bird communities traverse state, provincial, and national borders. -NABCI Tri-national website How were BCRs developed and how are they maintained? BCRs were developed initially from 1998 to 1999 by a mapping team comprising members of the United States, Mexico, and Canada. BCR s were defined through a process of expert consultation whereby CEC polygons from various scales were combined or split to create units corresponding to bird species distribution and requirements, and recognizing practical planning considerations. It was understood that updates to the BCR layer would be made every three years, but this did not begin to occur in an official capacity until The USFWS created the original BCR layer (Arc/INFO format) in 1999 with help from Bird Studies Canada (BSC). BSC has hosted the master copy of the file on its website ever since. Following initial use of the layer, some inconsistencies were found, at which point Environment Canada made substantial edits to the base map (primarily to improve the resolution of the Canadian coastline). Subsequently, BSC made further edits to the base map, embedded lakes, and attributes; and made other fixes to improve the utility of the layer for analysis purposes (e.g., range map analyses for the Partners in Flight Species Assessment). Changes to Canadian BCRs, as requested by NABCI Canada, were also incorporated. Bird Studies Canada continues to be the authoritative keeper of the master BCR file and maintains and distributes the layer as an in-kind service to NABCI. In the near future, BSC will develop a new webpage where the updated map layer can be viewed interactively or downloaded (in a variety of spatial and graphic formats) and where all changes to the BCRs will be documented, including those noted below. Changes to US BCRs As part of a formal review process led by US NABCI, beginning in 2009, six changes were proposed for US BCRs. Upon review, proposed changes were either approved in their original state, or approved with modifications. These were then sent to BSC for implementation. The changes have now been completed and are described in detail in this document.

3 BCR 28 (APPALACHIAN MOUNTAINS) AND 30 (SOUTHERN NEW ENGLAND/MID- ATLANTIC) Proposers Andrew Milliken, Brian Smith, Catherine Rideout Description Use the boundary between the states of NY and CT to delineate the northeastern limit of BCR 28. The finger that protrudes up through CT and MA is an extension of the Green Mountains to the north, which aligns more closely with systems in BCR 30. A Level IV ecoregion line may delineate an ideal ecological boundary in this general area, but Level IV ecoregion boundaries have not been drafted in NY yet. As proposed, this accurately represents how planning efforts for ACJV and AMJV are being conducted. Decision Alternative Recommendation. We recommend that the boundary between BCR 13 (Lower Great Lakes/St. Lawrence River) and 14 (Atlantic Northern Forests) be extended south, therefore putting the spur (pico) of BCR 28 that is the subject of debate into one or both of these BCRs and following level III lines. Justification The subcommittee was not comfortable with a proposed new boundary following a state/political boundary (in this case, the NY-CT state line). Status change made Since Omernik s level IV lines are now available for this area and since following a state boundary is not desirable, we used the level IV line adjacent (West) of the state line to place the large part of the finger that has the Green Mountains into BCR 30 (yellow) and leave the remaining piece in BCR 28 (green). This removes the need to use a political boundary or arbitrarily draw a line more southward. 2

4 Figure 1. Before-after maps showing changes to BCR 14, BCR 28, and BCR 30 3

5 Figure 2. Proposed changes presented by BSC to the Committee 4

6 Figure 3. Original proposed map 5

7 BCR 27 (SOUTHEASTERN COASTAL PLAIN), 28 (APPALACHIAN MOUNTAINS), AND 29 (PIEDMONT) Proposer(s) Andrew Milliken, Brian Smith, Catherine Rideout Description For all but the Talledega National Forest (i.e., TNF should remain in BCR 28), follow the Level III ecoregion boundaries to delineate the Appalachian Mountains, the Piedmont, and Southeastern Coastal Plain BCRs in the southernmost portion of the original BCR 28 boundary. This is an ecologically diverse/complex area, but everything south/southeast of TNF transitions into elevations and systems more closely associated to Piedmont/Coastal Plain than the Appalachians. Decision Approved Justification The original BCR 28 boundary is arbitrary in what was included in the southeastern-most portion of the BCR. Evaluating elevation bands, DEMs, and Level III ecoregion boundaries simultaneously has provided a more realistic representation of the transitions among BCRs 27, 28, and 29 in Alabama. Following Level III ecoregion lines best represents the area, except that Talledega NF should remain within BCR 28 because it encompasses the last ridges of the Ridge and Valley ecoregion and has elevations/bird communities more closely associated to nearby portions of BCR 28. The subcommittee accepts this reasoning, but would like verification of exactly where the level III line boundaries are in relation to these proposed changes. Status change made The line shown in the proposed map shown further below as A B, designed to exclude the Talladega National Forest from the new portion of BCR 29 (Piedmont), was not the most scientifically-sound way to redefine the BCRs. However, there were no ecoregion levels or contour lines that could guide another way. After discussion with the Joint Venture coordinator and the US NABCI coordinator, it was decided that this expert-informed line would be used and a shapefile was obtained to outline it accurately. The shapefile also followed the level IV line down further along the boundary between BCRs 27 and 29, so this was completed as well. 6

8 Figure 4. Before-after maps showing changes to BCR 27, BCR 28, and BCR 29 7

9 Figure 5. Original proposed map 8

10 BCR 12 (BOREAL HARDWOOD TRANSITION), 23 (PRAIRIE HARDWOOD TRANSITION) AND 22 (EASTERN TALLGRASS PRAIRIE) Proposer Barbara Pardo Description The change would place the Lake Huron and Erie Plains into the Prairie Hardwood Transition (BCR 23) and remove them from the Boreal Hardwood Transition (BCR 12) and Eastern Tallgrass Prairie (BCR 22). Decision Approved Justification Historically the Lake Huron and Erie Plains were dominated by forested wetlands (swamp). The Lake Huron Plain may have been well placed into the Boreal Hardwood Transition (BCR 12) before European settlement, because it was heavily forested. However, the sub-region was converted to agriculture in the early 1900s and it will likely remain in crop production due to the high productivity of the soils. In addition to forested wetlands, the Lake Erie Plains (currently in Eastern Tallgrass Prairie, BCR 22) historically included interspersed pockets of savanna pre- 1900s. This area is also now heavily influenced by agriculture due to its productive soils. Currently, both these sub-regions provide high value to breeding and non-breeding waterfowl, waterbirds, and shorebirds, thus the majority of conservation actions in these regions are focused on emergent (non-forested) wetland protection, restoration, and management. These current bird communities and conservation activities are more indicative of conservation planning, design, and implementation for the Prairie Hardwood Transition. Changing the Prairie Hardwood Transition (BCR 23) boundary to encompass these two lake plain areas would allow for easier descriptions of priority bird needs and more logical conservation planning in all the BCRs influenced. In this case, removing the Huron Lake Plain from the Boreal Hardwood Transition (BCR 12) would allow BCR 12 to focus on management of forest bird communities in a region with large public ownership, without the distraction of priority wetland-dependent bird needs surrounding Saginaw Bay. Likewise, removing the Lake Erie Plain from the Eastern Tallgrass Prairie (BCR 22), would allow BCR 22 to focus on management of grasslands, bottomland forest, and key stopover sites (i.e., wetlands, grasslands, and forest patches) in a region with primarily private ownership. The Prairie Hardwood Transition (BCR 23) would gain the two sub-regions and would continue to focus on maintaining quality habitat for grassland/savanna, wetland, and forest dependent bird communities, in a matrix of public and private ownership. Status change made Omernik s level III polygons outline the proposed region changes and these changes were implemented. 9

11 Figure 6. Before-after maps showing changes to BCR 12, BCR22, and BCR23 10

12 Figure 7. One of the original proposed maps 11

13 BCR 37 (GULF COASTAL PRAIRIE) AND 26 (MISSISSIPPI ALLUVIAL VALLEY) Proposer Barry Wilson Description The proposed change would relocate the BCR 37/26 boundary further inland, so the entire coastal zone (as defined by the GCJV boundary and State of Louisiana Coastal Zone) falls within BCR 37. Decision Alternative Recommendation. The team recommends adjusting the lines between 37/26 to coincide with Omernik's level 4 lines. That would mean that all of 73o including Lake Pontchartrain would be in BCR 37 and 73n and 73k would be in BCR 26. The team understands that no line is perfect but believe this decision supports the needs of the Gulf Coast JV and also remains true to the BCR map. Justification The Gulf Coast JV's request was based on the need to more accurately reflect coastal marsh in BCR 37. The review team s main concern was that the line proposed by the JV Coast moves forested wetlands into BCR 37. Status change made Omernik level IV lines corresponding to 73o were used to divide BCRs 26 and 37. This procedure resulted in the specified alternative recommendation to have all of 73o in BCR 37 and all 73n and 73k in BCR 26. It did result in the loss of some Gulf Coastal Prairie BCR to the Mississippi Alluvial Valley BCR, so after discussion with Allison Vogt, it was decided that the best scenario would be to use the level IV line, with the exception of cases where using the 73o line would result in the loss of Gulf Coastal Prairie south of the original boundary (since the original goal was to actually move the boundary inland). 12

14 Figure 8. Before-after maps showing changes to BCR 26 and BCR 37 13

15 Figure 9. Original proposed map with arbitrary proposed line 14

16 BCR 30 (SOUTHERN NEW ENGLAND/MID-ATLANTIC) AND 27 (SOUTHEASTERN COASTAL PLAIN) Proposers Andrew Milliken, Brian Smith, Catherine Rideout Description Use the Chesapeake Bay Watershed Hydrologic Unit Code delineation (HUC) to place the entirety of the Chesapeake watershed into BCR 30; this divides the Chesapeake Bay drainage from those lands draining into Albermarle-Pamilico Sounds, including Back Bay, Great Dismal Swamp and the Chowan drainage, which should be included in BCR 27. Decision Approved Justification The existing BCR boundary between 30 and 27 makes no political or ecological sense because it divides the Chesapeake Bay watershed. The proposed change will allow the southeastern pine ecosystem that historically extended north to the section of southern Virginia drained by the Chowan, to become part of the Southeastern Coastal Plain BCR, along with the priority species, such as Red-cockaded Woodpecker and Bachman s Sparrow, whose northern range limit is the pine ecosystem. Leaving the habitats used by these species in the mid-atlantic effectively subordinates other priority species in BCR 30. Status change made The southern-most boundary of the lower Chesapeake watershed was used to cut BCR 27 into two pieces, the northern-most of which was reassigned to BCR 30 by editing the attribute table. 15

17 Figure 10. Map showing final changes to BCR 27 and BCR 30 with overlays to show the Chesapeake Bay and the original BCR 27 16

18 Figure 11. Original proposed map 17

19 BCR 21 (OAKS AND PRAIRIES) AND 25 (WEST GULF COASTAL PLAIN/OUACHITAS) Proposer James Giocomo Description Adjust the western border of BCR 25 and the eastern border of BCR 21 to match the current Omernik Level III ecoregion boundaries. Decision Approved Justification Current planning efforts in the OPJV (Oaks and Prairies Joint Venture) and the LMVJV (lower mississipi valley joint venture) use the BCR lines and not the administrative lines included in the recent USFWS Joint Venture map. The administrative boundaries are based upon county boundaries and pre-date the establishment of the Oaks and Prairies Joint Venture. The proposed border change will better align BCR boundaries with habitat on the ground. Status change made Omernik s level III regions were used to cut BCR 21 and BCR 25 into multiple polygons which were then edited so that they would have the value of the appropriate BCR (West of level III line = BCR 21, East = BCR 25). 18

20 Figure 12. Before-after maps showing changes to BCR 21 and BCR 25 19

21 Figure 13. Original proposed map 20

Unit 1: Geography. For additional information, refer to this website: 1 G e o g r a p h y

Unit 1: Geography. For additional information, refer to this website: 1 G e o g r a p h y Unit 1: Geography For additional information, refer to this website: http://mryoungtms.weebly.com/ 1 G e o g r a p h y Continents and Oceans SOL USI. 2a Essential Understanding: Continents are large land