Limits...
Nest relocation and excavation in the Florida harvester ant, Pogonomyrmex badius.

Tschinkel WR - PLoS ONE (2014)

Bottom Line: Relocation is probably intrinsic to the life history of this species, and the causes of relocation remain obscure--the architecture of old and new nests was very similar, and neither the forest canopy nor the density or size of neighbors was correlated with relocation.Colonies moving more than once in two years lost more size than those moving less often, suggesting that moving may bear a fitness cost.Colony relocation is a dramatic and consistent feature of the life history of the Florida harvester ant, inviting inquiry into its proximal and ultimate causes.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Science, Florida State University, Tallahassee, Florida, United States of America.

ABSTRACT
The Florida harvester ant (Pogonomyrmex badius) excavates deep nests in the sandy soils of the Gulf and Atlantic coastal plains. Nest relocations of over 400 colonies in a north Florida coastal plains pine forest were tracked and mapped from 2010 to 2013. Individual colonies varied from one move in two years to four times a year, averaging about one per year. Almost all moves occurred between May and November peaking in July when more than 1% of the colonies moved per day. Move directions were random, and averaged 4 m, with few moves exceeding 10 m. Distance moved was not related to colony size. Over multiple moves, paths were random walks around the original nest location. Relocation is probably intrinsic to the life history of this species, and the causes of relocation remain obscure--the architecture of old and new nests was very similar, and neither the forest canopy nor the density or size of neighbors was correlated with relocation. Monitoring entire relocations (n = 20) showed that they were usually completed in 4 to 6 days. Moves were diurnal, peaking in the mornings and afternoons dipping during mid-day, and ceasing before sundown. Workers excavated the new nest continuously during the daytime throughout the move and beyond. A minority of workers carried seeds, charcoal and brood, with seeds being by far the most common burden. The proportion of burdened workers increased throughout the move. Measured from year to year, small colonies gained size and large ones lost it. Colonies moving more than once in two years lost more size than those moving less often, suggesting that moving may bear a fitness cost. Colony relocation is a dramatic and consistent feature of the life history of the Florida harvester ant, inviting inquiry into its proximal and ultimate causes.

Show MeSH
The frequency distribution of the number of moves by colonies in 2012 and 2013.The increase in the number of moves in 2013 compared to 2012 resulted from a decrease in the number of colonies that did not move, and an increase in those that moved multiple times.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4237378&req=5

pone-0112981-g003: The frequency distribution of the number of moves by colonies in 2012 and 2013.The increase in the number of moves in 2013 compared to 2012 resulted from a decrease in the number of colonies that did not move, and an increase in those that moved multiple times.

Mentions: During 2012–13, 473 colonies were observed to relocate 841 times (Fig. 3). During 2012 colonies moved an average of 0.72 times, but in 2013, the average was 1.15 times, significantly higher (t-test: t903 = 8.27, p<0.00001), The frequency distributions were significantly skewed in both years as many colonies moved multiple times (skew = 0.54 and 0.64, respectively, s.e. = 0.11). In both years, about 200 colonies moved only once. The higher mean in 2013 was the result of a decrease in the number of colonies that did not move, and an increase in those moving more than once, with some colonies moving up to 4 times.


Nest relocation and excavation in the Florida harvester ant, Pogonomyrmex badius.

Tschinkel WR - PLoS ONE (2014)

The frequency distribution of the number of moves by colonies in 2012 and 2013.The increase in the number of moves in 2013 compared to 2012 resulted from a decrease in the number of colonies that did not move, and an increase in those that moved multiple times.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4237378&req=5

pone-0112981-g003: The frequency distribution of the number of moves by colonies in 2012 and 2013.The increase in the number of moves in 2013 compared to 2012 resulted from a decrease in the number of colonies that did not move, and an increase in those that moved multiple times.
Mentions: During 2012–13, 473 colonies were observed to relocate 841 times (Fig. 3). During 2012 colonies moved an average of 0.72 times, but in 2013, the average was 1.15 times, significantly higher (t-test: t903 = 8.27, p<0.00001), The frequency distributions were significantly skewed in both years as many colonies moved multiple times (skew = 0.54 and 0.64, respectively, s.e. = 0.11). In both years, about 200 colonies moved only once. The higher mean in 2013 was the result of a decrease in the number of colonies that did not move, and an increase in those moving more than once, with some colonies moving up to 4 times.

Bottom Line: Relocation is probably intrinsic to the life history of this species, and the causes of relocation remain obscure--the architecture of old and new nests was very similar, and neither the forest canopy nor the density or size of neighbors was correlated with relocation.Colonies moving more than once in two years lost more size than those moving less often, suggesting that moving may bear a fitness cost.Colony relocation is a dramatic and consistent feature of the life history of the Florida harvester ant, inviting inquiry into its proximal and ultimate causes.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Science, Florida State University, Tallahassee, Florida, United States of America.

ABSTRACT
The Florida harvester ant (Pogonomyrmex badius) excavates deep nests in the sandy soils of the Gulf and Atlantic coastal plains. Nest relocations of over 400 colonies in a north Florida coastal plains pine forest were tracked and mapped from 2010 to 2013. Individual colonies varied from one move in two years to four times a year, averaging about one per year. Almost all moves occurred between May and November peaking in July when more than 1% of the colonies moved per day. Move directions were random, and averaged 4 m, with few moves exceeding 10 m. Distance moved was not related to colony size. Over multiple moves, paths were random walks around the original nest location. Relocation is probably intrinsic to the life history of this species, and the causes of relocation remain obscure--the architecture of old and new nests was very similar, and neither the forest canopy nor the density or size of neighbors was correlated with relocation. Monitoring entire relocations (n = 20) showed that they were usually completed in 4 to 6 days. Moves were diurnal, peaking in the mornings and afternoons dipping during mid-day, and ceasing before sundown. Workers excavated the new nest continuously during the daytime throughout the move and beyond. A minority of workers carried seeds, charcoal and brood, with seeds being by far the most common burden. The proportion of burdened workers increased throughout the move. Measured from year to year, small colonies gained size and large ones lost it. Colonies moving more than once in two years lost more size than those moving less often, suggesting that moving may bear a fitness cost. Colony relocation is a dramatic and consistent feature of the life history of the Florida harvester ant, inviting inquiry into its proximal and ultimate causes.

Show MeSH