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Funding Available for Urban Conservation Gardens and High Tunnels Applications for the Urban Conservation Project…

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REMAINING December 2017 Chapter Meetings and those planned for January & February, 2018: Please monitor chapter pages (links below) and News & Events pages!…

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Tuesday, 7-8:30 pm San Antonio NPAT Chapter Monthly Meeting“MISSION REACH Ecosystem Restoration and Recreation Project”,  Environmental Sciences, San Antonio…

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WATCH THE SKYS!  POLLINATOR MIGRATIONS ARE BEGINNING!

Tuesday, Aug 01, 2017

WATCH THE SKYS!  MIGRATIONS ARE BEGINNING!

MONITOR “LIVE” ON WEBSITES!

As we progress through the upcoming weeks of our LONG – HOT SUMMER, we can observe some of our feathered friends as they fly south to their winter homes in Central America and South America. 

Migrations begin for the Purple Martins, Hummingbirds, Monarch Butterflies, and Mexican Free-tailed Bats (just to name a few, plus swallows, cranes, and many more)!  Some of the migrations can be observed online thanks to some very clever technology:

MIGRATIOIN OF MONARCH BUTTERFLY Danaus plexippus

Observe the Monarch Migration - Report Summer Sightings on the U.S. Forest Service’s migration map!

Early Spring to Late Summer Timeline:
In late February or early March Monarch Butterflies awake from hibernation where they’ve been in the protected forests of oyamel fir trees in Central Mexico. They find a mate and begin the long journey northward for to spend spring and summer in warmer climates and pollinate plants as they travel to north or northeast areas of North America (U.S. and Canada).  Each generation lives 2-6 weeks; each progresses northward during those weeks, each generation will live long enough to lay eggs, then it dies.

The fourth generation begins migrating southward in early autumn; they must fly thousands of miles (taking several weeks) to reach their destination in Central Mexico by November.  There they will hibernate until late February or early March when they will mate and begin the long journey northward. (We have observed spring arrivals in Central Texas; they like to lay their eggs on milkweed plants.) Remember each generation (first, second, and third) usually lives no longer than a period of 6 weeks, during which they have mated, laid their eggs, and died. Some of the fourth generation fly as far north as Canada by May and June.

MIGRATE SOUTH FOR WINTER The Monarch Butterfly cannot survive cold winters of northern climates, so in early fall, monarchs living in eastern North America migrates south, funneling through Texas and hugging the Gulf Coast on their way to central Mexico.  The last generation is responsible for the Monarch Butterflies’ survival: it MUST fly to Central Mexico so they can hibernate over the winter months!  It is amazing to realize these butterflies have never flown the southern migration route nor seen the oyamel fir tree forest in Central Mexico.  (They were all born in far North America months after their ‘ancestors’, the first, second and third generations made their journeys living just long enough to mature, mate, and lay eggs of future generations before dying.  Each newly hatched generation lived to fly its portion of the journey.)  The entire Monarch Butterfly population will hibernate in fewer than 20 sites within the exact same oyamel fir trees in which their ancestors hibernated.  Imagine 20-30 million in clusters to keep warm. 
Photo of Oyamel Fir Tree in Central Mexico:

MIGRATION of the MEXICAN FREE-TAILED BAT Tadarida brasiliensis

“BAT-WATCH” LIVE!
Texas Parks & Wildlife Department collaborated with Bat Conservation International and recently introduced the site: Bat-Watching Sites of Texas!   It highlights 12 Texas bat-watching sites (4 are TPWD properties!) and covers general bat biology, lists bat species in Texas, discusses white-nose syndrome (WNS), and explains bat-watching etiquette.

The Nature Conservancy wrote that the Eckert James River Bat Cave is one of the largest bat nurseries in the country. Photo of Bats near the Eckert James River Bat Cave:

Mexican free-tailed bats are the most common bat found throughout Texas. These mammals are VERY BENEFICIAL, as they are agents of seed dispersal and cross-pollination for many plant species.  They join other beneficial pollinators, purple martins, hummingbirds and swallows, in helping control insect populations!  Each bat consumes close to its body weight in insects (they eat mosquitoes and numerous crop pests such as cutworm and corn borer moths).  Like the Monarch Butterflies, the bats, who are mammals, also winter in Mexico, but they settle into and remain in caves!  Mexican free-tailed bats begin their migration southward in October through mid-November (when the first cold fronts start to push through).  Like the monarchs, they also fly to central Mexico, but they spend the winter in caves.  Then in February they begin their northward migration to Texas.

The female bats form large “maternity colonies” where they will raise their young.  They require high humidity and high temperature levels (so Texas is perfect)! 
Once the bats mate, the male bats move into their new, smaller “bachelor colonies”.  They live away from females and pups and are not involved in raising the young.
The mother bats’ milk is very rich; so within 4-5 weeks they have grown and are ready to fly.  The mothers and pups remain in the ‘maternity colonies’; it gets VERY crowded. They roost in densities of up to 500 pups per square foot. The mother has miraculous hearing; each mother can return from eating insects and fly directly into the cave to her own baby by using her sense of smell and knowing the sound of their pup’s call.

Then, when the first cold fronts start pushing through in late October to mid-November, the Mexican free-tailed bats begin their migration to Mexico for the winter.

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