maryland’s next ten species phil davis 25 june 2009 being

8/14/2019 Marylands Next Ten Species Phil Davis 25 June 2009 Being

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Marylands Next Ten Species

Phil Davis

25 June 2009

Being a systems engineering computer type by background and training (OK, anal-retentive

OK, a nerd! OK, a geek!!!) I couldnt just approach this task randomly or go by gut I feltcompelled to develop some logical methodology to use in deriving my top ten picks.

I thought about it and came up with, what I call my bulls eye methodology. I placed Marylandat the center of a bulls eye and then identified a Zone 1 that surrounded Maryland consisting

of the contiguous states of DE, VA, DC, WV, and PA. I then analyzed the official state lists ofeach Zone 1 state and identified species that were on those states lists but were not on

Marylands list. I gave each of those hits a value of 100 points. Next, I laid out a Zone 2consisting of the next closest ring of states: NC, OH, NY, and NJ. Similarly, I identified species

from those states lists that were not on Marylands list and gave each hit a value of 50 points.

Bulls Eye Methodology Zones 1 and 2


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Later, I decided to extend this model a bit further by adding a Zone 3 consisting not of the next

ring of states, but rather the islands of the northern Atlantic Ocean since many vagrants reachNorth American landfall by direct overwater flights. So, Zone 3 consisted of Greenland, Iceland,

the Azores, Bermuda, and the Bahamas. I valued each species from this zone at 25 points per hit.

I admit, when I initially added Zone 3, I was actually more interested in developing a list ofpotential North American firsts that could, theoretically reach Maryland. However, after Iadded Zone 3, I found that these islands contributed species to the model that actually amplified

the data values already imparted by Zones 1 and 2.

Bulls Eye Methodology Zone 3

Obviously the assignment of 100, 50, and 25 points is a rather random approach to weighting the

distribution contribution of each zone, but at least it has some logic behind it. I then decided toadd a few more parameters to my model.

First, I added two factors that defaulted to a value of 1.00, therefore having no effect on the total

points unless I increased or decreased the factors. These two factors were for Detection andIdentification. Detection deals with the probability that a species will be detected in Maryland.


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An example of where I decreased the Detection factor to .75 is for MacGillivray's Warbler sincethis species is a skulker . Conversely, Northern Hawk Owls tends to sit out in the open on the top

of dead snags during the daytime, increasing their chances of being detected; so for this species Ielevated the Detection parameter to 1.25. For the Identification factor, I increased the value for

species such as White-cheeked Pintail, which is very distinctive bird. On the other hand, for

Pacific Golden-Plover I decreased the Identification factor down to .75 due to its similarity toAmerican Golden-Plover in the fall.

Next, I added a Trend factor, which also defaulted to 1.00, a null value. For species where thetrend in records has been down over the past years, I reduced the factor to a lower value. An

example of a decreasing trend is Shiny Cowbird where there was a spate of records in the 1990s,but records have been few and far between north of Florida in recent years; therefore I decreased

the trend factor for this species to .75. Likewise, I increased the trend factor for a few species,such as Ivory Gull and Pink-footed Goose, since there have been more northeastern records in

recent years.

Finally, I added a set of factors for Habitat/Range that provided me with the abi lity to attenuatescores in subcategories of Pelagic, Coastal, Coastal Plain, Piedmont, Ridges and

Valleys, Boreal, and Prairie. Defaulting to a null value of 1.00, I decreased the factor for afew species. For example, Prairie Falcon enters the model from a Zone 2 hit from Ohio; however

since Marylands prairie habitat is limited (!), I decreased the value of this factor.

I could have made this even more complicated (really?!) by factoring in the number of records ineach jurisdiction, season distributions, the relative sizes of the states, or the ratios of shoreline,

but this was already getting out of hand, even for me! So, instead of creating the equivalent ofclimate change model, I yelled Uncle and stopped development and when into production.

After running the model a couple of times and tweaking a few of the factors,, I came up with my

results the envelope please

1. Brambling (350 points). While there is only one Zone 1 record (PA), all of the Zone 2 stateshad have records (NJ, NY, OH, and NC). Furthermore, Zone 3 records come from Iceland and

the Azores. Prediction: Location: Finzel Swamp; month: January, finder: JB Churchill.

2. Garganey (325 points). Records exist in Zone 1 only for DE; however, in Zone 2, there arerecords for NJ, NC, and OH. While detection of a male should be straightforward, a female

record would be more challenging. Maryland has had Garganey in the state before, however;they were dismissed (sigh!) as escapes. Prediction: Location: Blackwater NWR; month: May,

finder: Jim Brighton.

3. Black-tailed Godwit (319 points). Zone 1 records include DE and PA (actually PA is underconsideration). Zone 2 records are from NJ. NY, and NC. Zone 3 contributes Greenland,

Iceland, and the Azores. I reduced the Range/Habitat factor to .75 due to Marylands decliningprofile of good wetlands. Prediction: Location: West Ocean City pond; month: June, finder: John

Hubbell.


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4. Bell's Vireo (300 points). There was only a V A hit from Zone 1; however, in Zone 2 each ofthe states (NY, NJ, OH, NC) had records. Nothing doin in Zone 3. Prediction: Location: Big

Pool; month: May, finder: Hans Holbrook.

5. Ivory Gull (293 points). Nothing in Zone 1. Zone 2 records include NJ, NY , and OH. Zone 3

records are from Greenland and Iceland. I increased the Detection factor to 1.25 since these birdsare distinctive and the Identification factor to 1.25 since they are easy to ID. I set the Trendfactor 1.25 since records seem to be in the lower 48 (maybe because of displacement due to

melting arctic ice?). I reduced the Range/Habitat factor to .75 due to a lack of seashore locationswhere an Ivory Gull might find scraps to scavenge upon. Prediction: Location: Conowingo Dam;

month: January, finder: Gene Scapulla.

6. Eurasian Woodcock (275 points). There is only a single hit in Zone 1 for VA and two hits inZone 2 for NY and OH. However, Zone 3 had three hits: Greenland, Iceland, and the Azores.

Prediction: Location: Deal Island; month: Jan, finder: Stan Arnold.

7. White-tailed Kite (250 points). Again, a single Zone 1 hit for V A. Zone 2 hit it big with NJ,NY, and NC. Zone 3 added none. Prediction: Location: Ft. Smallwood; month: Jun, finder: Sue

Ricciardi.

8. Lewis's Woodpecker (250 points). (I arbitrarily broke the tie for 7th

place.) In Zone 1 thereare hits for VA and P A. Zone 2 added NY. Zone 3 - none. Prediction: Location: Lily Pons;

month: Dec, finder: Gail Mackeirnan and Barry Cooper.

9. Bar-tailed Godwit (244 points). Zone 1s only contribution was only for VA. Zone 2garnered points from NJ, NY, and NC. In addition, Zone 3 contributed Iceland, Azores, and

Bermuda. Again, I reduced the Range/Habitat factor to .75 due to Marylands relative lack ofgood shoreline. Prediction: Location: Assateague Island; month: Jul, finder: Mark Hoffman.

10. White-winged Tern (239 points). Zone 1 had records for VA and DE. Zone 2s records were

for NJ, NY, and NC. Zone 3 included Iceland, Azores, and the Bahamas. I reduced the Trendfactor to .75 since the number of records of this species has declined in the past decade. I also

reduced the Range/Habitat factor to .75 to a lack of extensive and accessible marshes along theshort Maryland coast line. Prediction: Location: Poplar Island; month: September, finder: Jan

Reese.

Next five honorable mentions (11 -15):11. Pink-footed Goose (234 points)

12. Snowy Plover (tied at 225 points)12. Sharp-tailed Sandpiper (tied at 225 points)

12. Fieldfare (tied at 225 points)12. Redwing (tied at 225 points)

Phil Davis

maryland’s next ten species phil davis 25 june 2009 being

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