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Sage Words About Wildlife: Climate Change Alters Hummingbird Migration

Sage Words About Wildlife: Climate Change Alters Hummingbird Migration

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Synopsis:

Nature doesn't come to a sudden, overall halt, when the timing of its ecosystems slip, including ones involving hummingbirds. Instead, change occurs gradually. Plants and the animals that pollinate them have coevolved to meet each other's needs. An example is the long beaks of hummingbirds and deep, tubular flowers. Both sides of this survival equation suffer when the phenology -- or timing -- of hummingbird and plant connections is thrown off. Recent scientific studies explore these shifts and climate change. You can help by planting hummingbird habitat in your home garden. We detail ten nectar-rich Salvias and companion plants that are hummingbird favorites.

Systems that work smoothly are important whether in your car or nature.

In a car, a timing belt connects the engine's camshaft and crankshaft to synchronize their movement and keep things running smoothly. Break the belt, and you break the rhythm, or timing, of the engine. A number of bad things can happen, but the most obvious difficulty is that your car won't operate.

Nature doesn't come to a sudden, overall halt, when the timing of its ecosystems slip, including ones involving hummingbirds. Instead, change occurs gradually and causes declines in beneficial animal and plant populations.

Three recent scientific studies explore these shifts and the climate change that has likely caused them.

Changes in Migration and Pollination
Plants and the animals that pollinate them have coevolved to meet each other's needs. An example is the long beaks of hummingbirds and the deep, tubular flowers that they favor.

Both sides of this survival equation suffer when the phenology -- or timing -- of their connections is thrown off. Hummingbirds are hurting birds during migration and nesting season if they arrive too early or late for the bloom time of flowers that feed them. As to the plants, their populations also decrease without access to their usual pollinators at bloom time.

A study about hummingbird migration published in January 2013 in The Auk, the journal of the American Ornithological Society, shows that climate change is harming phenology. It is causing the Ruby-Throated Hummingbird (Archilochus colubris) to arrive weeks earlier, during northward migration, than it did decades ago. Ruby-Throats now show up at their nesting grounds 12 to 18 days earlier than they did from 1890 to 1969.

According to the Auk report, these changes likely are due to temperature increases in the winter habitat of the hummingbirds.

However, this shift in timing of migration doesn't necessarily match alterations in the cycles of plants and insects, which are also affected by temperature changes.

Food Chain Disruption
Hummingbirds rely on nectar for 90 percent of their diet. The other 10 percent is comprised of pollen and tiny insects, which aren't available if the birds arrive when bloom time is over or hasn't yet begun. This is called a food-chain disruption.

University of Arizona scientist Zack Guido says historical records indicate that spring bloom of shrubs in the Southwest may have sped up by 20 to 41 days from 1894 to 2004. This could have negative consequences for the shrubs as well as the animals that dine on their nectar and pollen.

Writing at the Southwest Climate Change Network website, Guido offers the example of a "crash" in numbers of the northeastern Tulip Poplar. This occurred, he says, because honeybees no longer can get to the blossoms of Tulip Poplars in time for pollination.

Dilemma of the Broad-tailed Hummingbird
Broad-Tailed Hummingbirds ( Selasphorus platycercus) have to set up camp fast these days in the Rocky Mountains. It used to be a good location for nesting, because of abundant Glacier Lilies. But according to a University of Maryland study published in the journal Ecology in 2012, the hummingbirds and lilies now are out of synch.

The researchers note that, during the past 40 years, increasingly earlier snowmelt has sped up first bloom of the lilies to 13 days before first arrival of the Broad-tailed Hummingbirds. If climate change continues at its current pace, the researchers say, the hummingbirds will completely miss first bloom of the lilies 20 years from now.

So where will the Broad-Tails go to feed their families or how will their taste in flowers change? At present, the answers to these questions are unknown.

Variations in Flight Plans
Changes in nectar availability may be causing some hummingbirds to shift course during migration. In 2011, the Chicago Tribune posted a number of articles about a mystery hummingbird at a backyard feeder in the community of Oak Park.

Eventually a scientist from Chicago's Field Museum was able to pluck some of the bird's tail feathers, run a DNA test and determine that it was a female Rufous Hummingbird from the West. Although the species isn't rare, it is unusual in Illinois.

The Oak Park homeowners continued filling their feeder with sugar water for the hummingbird until it finally headed on its way following rest and refueling.

This change in course from West to Mid-West isn't even close to the biggest shift hummingbirds have made since they first appeared on earth. In 2004, the Los Angeles Times noted a Science magazine report on the discovery of two ancient hummingbird skeletons in Germany. It's estimated that the skeletons are 30,000 years old. Before the discovery, scientists thought that hummingbirds had always been Western Hemisphere species.

Become a Citizen Scientist Hummingbird Tracker
Volunteers nationwide help gather information about annual hummingbird migrations. Some help scientists at research centers, including Arizona's Fort Huachuca and Oregon State University both of which are connected to the national Hummingbird Monitoring Network.

At these centers, volunteers help to capture, weigh and band hummingbirds while also checking for signs of ill health. Volunteers in other programs, such as the Texas Hummingbird Round-Up, keep observation notebooks and file information annually.

Smartphones and computer pads are becoming tools for tracking hummingbird activity. Apps are available from the Audubon Society's Hummingbirds at Home program and from the Annenberg Foundation's Hummingbird Journey North education website.

Long-Blooming Hummingbird Gardens
One major way to aid preservation of hummingbirds is by planting wildlife habitat in your yard. If you would like to read about how to do it, here is one of our earlier blog posts on creating hummingbird habitat.

Past postings also include an article on careful use of water features and hummingbird feeders, which can help decrease garden bird battles by providing more supply for demand. However, don't over-rely on feeders. A hummingbird garden should include plenty of nectar-rich plants -- such as Salvias -- with tubular flowers built for hummer beaks.

To give hummingbirds an edge in overcoming phenological problems of not arriving in time for favorite nectar sources, it helps to plant long-blooming species, such as Salvias. Here are eight favorite choices, including two Salvia companions.

When citing height in our catalog and blog, we often give a range, because many Salvias increase in height when their flower spikes emerge. Please note that the second figure in a height measurement refers to how tall the plant is when in bloom.

Anise Hyssop (Agastache rugosa 'Heronswood Mist') Zones 5 to 9

  • Lavender flowers bloom summer to fall
  • 48 inches tall, 36 inches wide
  • Fragrant, heavily veined green leaves with purplish undersides sometimes
  • Full sun
  • Heat and drought tolerant
  • Also attracts butterflies and honeybees

Pink Cardinal Flower (Lobelia 'Monet Moment' ) Zones 6 to 10

  • Hot pink flowers bloom late summer to fall
  • 16 to 36 inches tall, 20 inches wide
  • Mid-green foliage
  • Full sun to partial shade
  • Water loving
  • Also attracts butterflies

Chiapas Sage (Salvia chiapensis) Zones 7 to 11

  • Magenta flowers bloom spring to fall
  • 36 to 48 inches tall, 36 inches wide
  • Mid-green, pebbly foliage
  • Full sun to partial shade
  • Average watering based on local climate

Red Velvet Sage (Salvia confertiflora) Zones 8 to 11

  • Hot orange-red flowers bloom
  • 60 inches tall, 36 to 48 inches wide
  • Red stems and bright green foliage
  • Full sun to partial shade
  • Average watering based on local climate
  • Also attracts butterflies

Mexican Green & Scarlet Sage (Salvia gesneriiflora 'Green Calyx Form')

  • Orange-red flowers bloom winter to spring
  • 72 inches tall and wide, dwarf form
  • Mid-green, somewhat heart-shaped leaves
  • Full sun
  • Average watering based on local climate
  • Also attracts honeybees

Gravid Sage (Salvia gravida) Zones 8 to 11

  • Long, hot pink flowers bloom in winter
  • 48 to 60 inches tall, 36 inches wide
  • Fragrant, bright green foliage and burgundy calyxes
  • Full sun to partial shade
  • Water loving

Cold Hardy Pink Sage (Salvia greggii 'Cold Hardy Pink') Zones 5 to 9

  • Creamy, hot pink flowers bloom spring to summer
  • 24 inches tall and wide
  • Mid-green, smooth, oval-shaped leaves and red calyxes
  • Full sun to partial shade
  • Heat and drought tolerant
  • Also attracts butterflies

Delicate Lady Autumn Sage (Salvia greggii 'Senorita Leah') Zones 7 to 9

  • Hot pink and red bicolor flowers bloom spring to fall
  • 24 inches tall and wide
  • Small, smooth, oval-shaped, green leaves
  • Full sun to partial shade
  • Heat and drought tolerant

Big Pitcher Sage (Salvia pitcher grandiflora) Zones 4 to 9

  • Deep violet to powder blue flowers bloom in fall
  • 48 to 60 inches tall, 24 inches wide
  • Bright green, grass-like foliage
  • Full sun to partial shade
  • Heat and drought tolerant
  • Also attracts butterflies and honeybees

Big Sheet Mountain Sage (Salvia microphylla 'Hoja Grande') Zones 7 to 9

  • Drooping Magenta flowers bloom spring to fall
  • 48 inches tall and wide
  • Fragrant, mid-green pebbly foliage
  • Full sun to partial shade
  • Heat and drought tolerant
  • Also attracts butterflies and honeybees

Buzz Us for More Information
While thoughts of hummingbird gardening whir through your mind, you may have some questions we haven't answered here. That's okay. Feel free to buzz us by email or telephone, and we will be glad to share what we know. You can also let us buzz in with alerts and special offers by subscribing for our free newsletter subscriptions. We promise not to hover too much.


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