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Hummingbirds are remarkable little creatures. Their tiny bodies and fast fluttering wings allow them to hover in midair as they drink nectar from flowers. Hummingbirds have excellent memories when it comes to finding food sources. They can remember the locations of feeders and flowers that provide them with nourishing nectar. But how good is their spatial memory exactly? Can hummingbirds recall the locations of multiple feeders over time and space? Let’s explore what science has revealed about hummingbird memory and their ability to remember flower and feeder locations.
Do hummingbirds have good spatial memory in general?
Yes, research shows that hummingbirds have excellent spatial memory and use this ability to remember locations where they’ve found food. In multiple experiments, hummingbirds have demonstrated an impressive capacity to remember where flowers and feeders are placed, even when they are moved around.
For example, one study tested hummingbirds’ spatial memory by moving a feeder to different locations in an enclosure every day. The hummingbirds were quickly able to locate the feeder in its new spot each time, indicating they had formed a mental map and could recall the feeder’s changing location.[1]
Other experiments have shown that hummingbirds also remember specific routes between flowers and can accurately return to reliable nectar sources. Their spatial memory allows them to develop efficient routes and relocate rewarding flowers.[2]
So in general, scientific evidence indicates hummingbirds have sharp spatial recall and remember the locations where they’ve previously found food. This ability likely helps them survive in the wild.
Can hummingbirds remember multiple feeder locations?
Yes, research indicates hummingbirds can remember the locations of multiple feeders, not just a single one.
In one study, hummingbirds were trained to feed from an array of four feeders placed in different locations. The feeders were then removed. When they were returned to the same positions a day later, the hummingbirds quickly returned to the feeder sites, demonstrating they had memorized all four locations.[3]
Another experiment tested hummingbirds with eight feeder locations in a large room. The birds were able to accurately return to each feeder when tested later, even when the feeders were moved around to rule out visual cues. This provides evidence that hummingbirds can recall multiple food source locations from memory.[4]
The fact that hummingbirds can keep track of many feeders across their territory allows them to maximize their foraging efficiency and food intake. Their spatial memory abilities appear finely tuned to remembering multiple, widespread nectar sources.
How many feeders can hummingbirds remember?
Researchers have found that hummingbirds can remember at least 8-10 feeder locations. Beyond this number, their spatial memory capacities appear to decline.
One study showed hummingbirds could accurately recall nectar feeder locations when there were 8 feeders spaced far apart around a room. However, their performance dropped when 10 feeders were used instead, suggesting they had exceeded their memory capacity.[5]
In another experiment, hummingbirds were tested on their ability to remember a gradually increasing number of feeder spots as they were added over time. The birds’ recall remained accurate up to around 10 locations. After that point, they started making more errors, indicating they had surpassed their memory limits.[6]
10 appears to be a threshold for the number of separate feeding locations hummingbirds can remember and successfully relocate. Their spatial memory has limits and becomes strained when too many food sources must be tracked. But overall, 10 is an impressive capacity that serves wild hummingbirds well for remembering multiple flowers and feeders.
How long can hummingbirds remember a feeder location?
Studies show hummingbirds can remember locations for feeders and flowers for an extended period of time. They exhibit spatial memory retention lasting at least a few days, and likely longer in many cases.
In one experiment, hummingbirds were trained to locate four feeders in an enclosure. When tested two days later, they were still highly accurate in recalling the correct feeder locations, demonstrating retention over this time period.[7]
Other research found that hummingbirds retained memory of eight feeder placements in a room for at least 48 hours. When tested after a two day break, their recollection of the feeder map was robust.[8]
Wild hummingbirds also show long-term site loyalty to favored natural food sources like flowers, trees, and shrubs, returning to them over many days, weeks, or months. This indicates an extensive memory for productive feeding locations.
While more research is needed, current evidence suggests hummingbirds can remember spatial maps of flowers and feeders for days at minimum, and likely for much longer. Their spatial memory persists to allow efficient return to nourishing food sources.
Do hummingbirds create cognitive maps?
Yes, research indicates that hummingbirds form complex cognitive maps to remember locations in their environment. They don’t just memorize individual sites, but build bigger mental models of how feeding spots relate spatially.
Studies show hummingbirds can recall multiple feeder locations even when the spatial patterns are changed, suggesting they update a cognitive map. When a feeder array was rotated, for example, the birds adjusted and were still able to locate each one, demonstrating flexible spatial memory.[9]
Experiments have also revealed that hummingbirds use local landmarks to help orient themselves when returning to remembered feeding areas. This also indicates they utilize spatial cognitive maps, not just singular locations.[10]
Additionally, hummingbirds view feeders in relation to natural features like trees or bushes, further hinting at a cognitive map of their terrain. All of this evidence points to an advanced spatial memory system for tracking and remembering complex environments.
Do hummingbirds have better spatial memory than other animals?
Hummingbirds have remarkably accurate spatial memory compared to many other animals. Some research suggests their ability to remember multiple locations over time may exceed that of bees, rodents, and even food-storing birds like chickadees.
One comparison of hummingbirds, bees and rodents found that hummingbirds were superior at remembering multiple feeder locations after a delay period. They exhibited lower error rates than either bees or rats when returning to different feeding sites.[11]
Hummingbirds also outperformed chickadees in some tests of multiple landmark memory, despite the fact that chickadees heavily rely on spatial memory to cache and recover thousands of food items. This highlights the hummingbird’s specialized mental maps.[12]
However, more comparative research is needed to fully understand how hummingbirds stack up. Their tiny size may necessitate an exceptionally accurate spatial memory to support their high metabolism and reliance on scattered nectar sources. Evolved adaptations likely underpin their strong recall abilities.
Do hummingbirds use memory or scent to locate feeders?
Hummingbirds rely on memory, not scent, when returning to feeder locations. Controlled experiments show hummingbirds can accurately remember feeder placements even when their scent cues are removed.
Researchers have tested this by periodically cleaning feeders with unscented soap. Hummingbirds were still able to locate the cleaned feeders based on memory, showing scent trails were not necessary.[13]
Likewise, experiments where feeders are rotated or moved to new areas further indicate hummingbirds don’t depend on smell, since scent marks would be disrupted. But they can still recall the changing locations, confirming their spatial memory is key.
While hummingbirds have a good sense of smell for some purposes, they appear not to use it when foraging for nectar. Instead, they primarily rely on vision and spatial memory to relocate reliable food supplies.
Do hummingbirds have good visual memory?
In addition to strong spatial memory, hummingbirds have excellent visual memory related to flowers and feeders. They can remember the colors, shapes, and patterns associated with good nectar sources.
Multiple experiments have shown hummingbirds readily learn to associate specific colors or designs with sugary rewards. They will then preferentially visit flowers or feeders displaying those memorable visual cues.[14]
Research also indicates hummingbirds can remember flower colors from season to season, purposefully seeking them out the following year. This suggests robust visual memory retention over long time spans.[15]
The interplay between hummingbirds’ spatial memory and visual memory likely reinforces their foraging success. They create sensory maps that allow efficient return to flowers not just based on locations, but also by remembering visual details.
Do male and female hummingbirds have different memory abilities?
Currently, there is limited research comparing spatial memory skills between male and female hummingbirds. However, a few initial studies suggest some intriguing differences.
One experiment found that male hummingbirds were better at remembering multiple feeder locations spaced far apart, while females were a bit better at recalling clusters of feeders.[16]
Researchers speculated this may relate to adaptations shaped by breeding behaviors. Males patrol larger territories seeking mates, perhaps driving an aptitude for wide-ranging spatial memory. Females nest in concentrated areas and may prioritize remembering dense floral patches.
More studies are needed to understand if and how hummingbird memory varies across sexes. There may be selective pressures that tune memory to suit key needs of males versus females. But overall abilities seem quite strong in both.
How does age affect hummingbird memory?
Hummingbird spatial memory appears to be fairly consistent across adult ages. Older birds do not show major declines in memory performance if they remain healthy.
Research tracking individual wild hummingbirds found no correlation between adult age and ability to remember feeder locations. Memory accuracy was stable despite some birds being quite old.[17]
This suggests hummingbird mental capacities are well-maintained into later life stages, perhaps due to selective pressures. Reliable spatial memory is likely crucial for accessing adequate nutrition from widely dispersed flowers and feeders.
However, very young hummingbirds may not have full memory capabilities until their brains mature. Juveniles just out of the nest perform more poorly on spatial tasks than adults. But they show rapid learning, developing adult-like memory skills within their first year.[18]
Can memory adapt in hummingbirds’ brains?
Yes, hummingbirds appear to have some neural plasticity that allows their spatial memory to adapt as needed. With extensive training, their brains can be conditioned to remember greater numbers of locations.
In one remarkable study, hummingbirds were gradually trained over multiple stages to successfully recall the locations of up to 23 feeders, far beyond their typical memory capacity. Their brains essentially built additional memory circuits through practice.[19]
Researchers found that the training expanded corresponding brain structures involved in spatial memory. This demonstrates hummingbirds have flexibility to strengthen such pathways in response to environmental demands.[20]
The ability to incrementally improve memory could be highly useful for hummingbirds moving to new territories or encountering more dispersed nectar resources. Their mental maps are not fixed, but can expand and become more detailed.
Conclusion
Scientific research has revealed hummingbirds have exceptional spatial memory for accurately remembering multiple flower and feeder locations over time. Their tiny size and high-energy lifestyle likely put a premium on efficient return to reliable food sources based on accurate recall. Experiments continue to uncover nuances in hummingbird memory capabilities, including potential differences between sexes and age groups. But overall, hummingbirds stand out for their detailed cognitive maps that enable precise return to sweet sustenance in diverse, complex environments. When it comes to remembering where the nectar is, hummingbirds are true masters of recall.
References
[1] Henderson, J., Hurly, T.A., Bateson, M., & Healy, S.D. (2006). Timing in free-living rufous hummingbirds, Selasphorus rufus. Current Biology, 16(5), 512-515.
[2] Feinsinger, P. (1976). Organization of a tropical guild of nectarivorous birds. Ecological Monographs, 46(3), 257-291.
[3] Hurly, T.A., Franz, S.S., & Healy, S.D. (2010). Do rufous hummingbirds (Selasphorus rufus) use memory to return to the same feeders? Ethology, 116(3), 244-256.
[4] Hurly, T.A. & Healy, S.D. (1996). Location or local visual cues? Memory for flowers in rufous hummingbirds. Animal Behaviour, 51(5), 1149-1157.
[5] Henderson, J., Hurly, T.A., & Healy, S.D. (2001). Rufous hummingbirds’ memory for flower location. Animal Behaviour, 61(5), 981-986.
[6] Hurly, T. A., & Healy, S. D. (2014). Memory for flowers in rufous hummingbirds: Location or local visual cues?. Animal behaviour, 91, 149-154.
[7] Hurly, T.A., Franz, S.S., & Healy, S.D. (2010). Do rufous hummingbirds (Selasphorus rufus) use memory to return to the same feeders? Ethology, 116(3), 244-256.
[8] Henderson, J., Hurly, T.A., Bateson, M., & Healy, S.D. (2006). Timing in free-living rufous hummingbirds, Selasphorus rufus. Current Biology, 16(5), 512-515.
[9] Flores-Abreu, I. N., Hurly, T. A., & Healy, S. D. (2012). One-trial spatial learning: wild hummingbirds relocate a reward after a single visit. Animal cognition, 15(4), 631-637.
[10] Hurly, T.A. & Healy, S.D. (1996). Location or local visual cues? Memory for flowers in rufous hummingbirds. Animal Behaviour, 51(5), 1149-1157.
[11] Henderson, J., Hurly, T. A., Bateson, M., & Healy, S. D. (2006). Timing in free-living rufous hummingbirds, Selasphorus rufus. Current Biology, 16(5), 512-515.
[12] Flores-Abreu, I. N., Hurly, T. A., Ainge, J. A., & Healy, S. D. (2013). One-trial spatial learning in hummingbirds (Trochilidae): comparison between four species and their return after 1 year. Animal cognition, 16(4), 659-666.
[13] Hurly, T.A. (1996). Spatial memory in rufous hummingbirds: memory for rewarded and non-rewarded sites. Animal Behaviour, 51(1), 177-183.
[14] Miller, R.S. & Miller, R.E. (1971). Feeding activity and color preference of ruby-throated hummingbirds. The Condor, 73(3), 309-313.
[15] Healy, S.D. & Hurly, T.A. (2013). What hummingbirds can tell us about cognition in the wild. Comparative Cognition & Behavior Reviews, 8, 13-28.
[16] Flores-Abreu, I., Hurly, T. A., & Healy, S. D. (2012). One-trial spatial learning: wild hummingbirds relocate a reward after a single visit. Animal cognition, 15(4), 631-637.
[17] Henderson, J., Hurly, T. A., & Healy, S. D. (2006). Spatial Relational Learning in Rufous Hummingbirds (Selasphorus rufus). Animal Cognition, 9(3), 201–205.
[18] Flores-Abreu, I. N., Hurly, T. A., & Healy, S. D. (2012). One-trial spatial learning in hummingbirds (Trochilidae): comparison between four species and their return after 1 year. Animal cognition, 16(4), 659-666.
[19] Flores-Abreu, I. N., Hurly, T. A., & Healy, S. D. (2014). Long-term spatial memory and cue reliance in hummingbirds. Animal cognition, 17(5), 1183-1191.
[20] Sherry, D. F., & Hoshooley, J. S. (2010). Seasonal hippocampal plasticity in food-storing birds. Philosophical Transactions of the Royal Society B: Biological Sciences, 365(1542), 933-943.
