Wednesday, January 11, 2012

Summary of the 2011 Gallon Jug CBC



The 2011 Gallon Jug Christmas Bird Count was held, in conjunction with the National Audubon Society, on December 31, 2011.  This marked the 22nd year of the Gallon Jug Estate Christmas Bird Count (GJE CBC) since it began in 1990.  Over the years there have been ups and downs in species, individual birds counted as well as in the number of participants.  Along with the variation in number of observers, there has been a range of good, bad and mixed weather conditions that influenced bird activity and detectability.

Species numbers have ranged from a low of 171 to 238 (Figure 1), averaging 203. Individuals  counted have previously ranged from 1718 to 4772 (Figure 2), averaging 2,849.  This was one of the years when intermittent heavy rain impacted bird detectability and bird activity as well as “observer” activity.  All participants experienced rain that seemed to begin just when we thought it was safe to step out of the vehicle again.

Given the slow start of the count day and the many hours of light to heavy rain, we were pleased that the 183 species recorded this year was not the lowest on record (2006 and 2007 were tied at a low of 171). However, the number of individuals counted was at an all time low with 1,646.  An additional 35 species were recorded for the Count Week, but not seen on the count day.

Figure 1.  Summary of unadjusted species recorded for each year of the GJE CBC.




Figure 2.  Summary of unadjusted individuals recorded for each year of the GJE CBC.

This year’s Top 20 are listed in Table 1 and can be compared with 2010.  During the 2010 CBC there were scant frugivores (= "fruit eaters") as a result of the impact of Hurricane Richard (October 24, 2010).  As the forest regenerates, the birds are returning and many of the frugivores that had evidently moved elsewhere in 2010, made it back into the Top 20 list for 2011.

The top species this year as in 2010, was the Ocellated Turkey. While the individual numbers recorded this year were somewhat lower, many were no doubt huddled out of sight under vegetation trying to stay dry.  This was not the case for many of the observers who were soaked to the skin.

Notably low this year with only 10 counted, was the Gray Catbird, ranked 5th in 2010 with 94 individuals. Last year the White-whiskered Puffbird was notable with a record 32 individuals recorded.  The average number of individuals of this species per count for the previous 20 years was only 9. This year we had none.  However, 2 White-necked Puffbirds were recorded.


Table 1. The 2010-2011 Top 20.  Comparison of species with the highest individual numbers.
2011


Species
Number

Ocellated Turkey
195

Olive-throated Parakeet
119

Montezuma Oropendola
116

White-collared Seedeater
63

Brown Jay
56

Red-lored Parrot
46

Tropical Kingbird
37

Cattle Egret
36

Social Flycatcher
35

Turkey Vulture
33

Roadside Hawk
30

Keel-billed Toucan
29

Rufous-tailed Hummingbird
26

Yellow-throated Euphonia
26

Pale-billed Woodpecker
24

Plain Chachalaca
21

White-breasted Wood-Wren
21

Black-headed Trogon
20

Melodious Blackbird
20



2010


Species
Number

Ocellated Turkey
273

Cattle Egret
219

White-collared Seedeater
114

Melodious Blackbird
102

Gray Catbird
94

Turkey Vulture
87

Killdeer
86

Tropical Kingbird
83

Montezuma Oropendola
58

Wood Thrush
56

Clay-colored Thrush
54

Brown Jay
52

Black Vulture
51

Olive-throated Parakeet
48

Mangrove Swallow
46

Vaux's Swift
44

Great-tailed Grackle
42

Ruddy Ground-dove
40

Blue-black Grassquit
39


We had a total of six parties (aka “teams” or groups counting birds) with a combined time of 34 observation hours. Party results ranged from a minimum of 20 to a high of 72 species and individuals ranged from 38 to 624. Last year the number of parties and hours counted were significantly higher.

In order to compare the CBC results over time, the data is standardized by the number of party hours for each species. This is how results are posted on the National Audubon Society's CBC  web site for each year’s results. Party hours for the GJE CBC have ranged from 22.75 to 77.25 with an average of 52 per count year. By using the data standardized per 50 hours, even  with reduced hours of counting due to the rain, this year’s count of individuals, while down a bit, was actually not bad.

 
Figure 3. 2011 GJE CBC summary based on standardized number of individuals.


Based on the effort all participants put forth and standardizing the data we actually had an increase in species per party hour over last year (Figure 4).  So while there were fewer of us for a shorter time, we counted more species than the teams did last year under considerably more favorable weather conditions.

 Figure 4. 2011 GJE CBC GJE CBC summary based on standardized number of species.


As always we thank all participants, including Chan Chich Lodge guests and guides, and our Corozal contingent who traveled to be here on Count Day.  One their way to Gallon Jug, they stopped at the rice fields near Blue Creek to see the Gadwalls and Redheaded ducks, rare species for Belize.  They reported that Gadwalls were still around but the Redheads had apparently moved on.

Thanks also to Chan Chich Lodge for their continued sponsorship of the GJE CBC. We wish to especially acknowledge Victor Emanuel Nature Tours as they have contributed to all of the GJE CBCs since the beginning.  Our special thanks go to VENT leaders Brian Gibbons and Bob Sunderstrom who provided the VENT trip report that contributed to the Count Week birds, as well as their efforts during the day of the count.

Submitted by:
Bruce W. Miller PhD.
Carolyn M. Miller MSc.
Gallon Jug, Belize
January 10, 2012

Friday, January 6, 2012

Rainy Day in the Neighborhood

If these vultures look a little dejected, it's because they are soaking wet and have been for the past few days.  Seems we had near record rain ... and over the Christmas Bird Count too.  Still, we managed to muster a few teams of hardy souls, braved the elements and conducted our count on 31 December.  Those of you facing snow and ice on your Christmas Counts likely do not feel too sorry for us.  Even so, torrential downpours beginning late morning and lasting throughout the afternoon put a "damper" on bird activity.  We are still tabulating "count week" birds and I'll post the results next week. Stay tuned!

Friday, December 30, 2011

Christmas Count Turkey

With the 112th Christmas Bird Count underway across the Americas, and the Gallon Jug 21st Christmas Bird Count coming up this weekend, I thought this bird would be an appropriate subject.  It is, of course, the Ocellated Turkey (Meleagris ocellata).  This colorful species has become something of an icon at Chan Chich Lodge, where a dozen can be seen at any given moment, and dozens more found in Gallon Jug.  On average, we record 119 each Christmas Bird Count.  The least we've counted was 37 (way back in 1990). And the overall best count for this near-threatened, endemic species in our count area  is 236 (see below).




Clearly, good management on the Gallon Jug Estate has helped the Ocellated Turkey thrive in Gallon Jug/Chan Chich.   Wonder if we'll break the record on Saturday?

Thursday, December 22, 2011

Jingle Bells -- Gallon Jug Style!

Every year we look forward to the Casey Community School Christmas carolers as they make the rounds in Gallon Jug and Chan Chich.  It's the official kick-off of the holiday season for us. And while it is true that there is no snow or ice, they lack nothing in holiday spirit. 

This year, teacher Miss Debbie composed a more "relevant" verse for the familiar favorite "Jingle Bells."  Listen carefully!  Those of you familiar with Belize's normal modes of transport will get a chuckle out of this one.

With Season's Greetings to Belize Field Notes readers from sunny Gallon Jug!

Friday, December 16, 2011

Sneak Peek

We finally got a good "hit" on our single camera. We'd placed it at a junction near Laguna Verde over the past week.  Any idea what this animal is?

This is a tayra, Eira barbara, taking a sneak peek at the remote camera.  The tayra is a large member of the weasel family and in my experience anyway, is not often photographed.  It's a common diurnal animal, very curious and bold and frequently encountered.  Tayras seem always to be in perpetual motion and it is my guess that they move so fast and frequently that the remote camera is just too slow to catch them.  In this case, there were several "blank" photos (after an image of its departing backside) indicating it was still in the immediate area.

Pretty clear than animals notice what's new in their environment, even if it is camouflaged!

Friday, December 9, 2011

Sure to be Counted


 This time of year, our thoughts turn to the annual Christmas Bird Count (see my November 18 post).  Pictured here, thanks again to Frank Buck, is a bird that will almost certainly be recorded on the Gallon Jug count: the Chestnut Woodpecker, Celeus elegans.   It is a species that, with a little effort, can be seen on any given day here in our neck of the woods.  This particular bird appears to be a  male with its red cheek patch -- females lack this.  Otherwise, the sexes appear alike.  They are richly chestnut in color, even orangish in brighter light.  The Chestnut Woodpecker is fairly large in size.  It prefers dead trees for nesting and foraging in good quality tropical forest which the Gallon Jug Estate and Chan Chich Lodge are fortunate to have.  Join us, if you'd like to see this attractive species.

Friday, December 2, 2011

Nocturnal Visitor

So we had this hole in our downstairs door.  And after a while, there was a sort of well-worn path to it.

Finally got the remote camera up last night ... and here's the culprit: an opossum.  We have a few different opossum species in Belize but so far as I can tell, this is the common Virginia opossum (Didelphis virginiana).  Found not only in Virginia, and the eastern half of the US, this adaptable creature's range extends all the way through Central America as well.  It is fairly frequently seen here in the Gallon Jug Estate. As you know from personal experience, this is a creature that often raids the garbage.  Fortunately for us, it so far has left our garbage untouched.