Mexico’s Monarch Butterfly Wintering Grounds

monarch butterflies

Monarch butterflies cluster tightly together in pine and fir trees in their Mexican habitat. (Photo credit: Getty Images)

The number of monarch butterflies overwintering in Mexico dropped by 27 percent in 2017, according to experts. This decline is a reversal in last year’s numbers, which appeared to show a recovery in the monarch butterfly population. [Read more…]

For the Birds: Seeking Sanctuary in Israel

white-throated kingfisher

This white-throated kingfisher is just one bird species that spends time in the Eilat sanctuary. (Photo credit: RGB Ventures LLC dba SuperStock/Alamy)

Depending on where you live, you might be able to look out  the nearest window and see or hear birds. If you look out the window and see snow, or know that if you went out you would feel the cold of winter, then chances are there are probably few birds to be seen, as they have likely migrated to a warmer climate until spring sends them winging back home.

Birds migrate according to differing patterns, schedules, and destinations that have evolved over millennia. Some species find their way, often to exactly the same nesting grounds every year, by using their keen eyesight to recognize landforms and geographic features, memorizing the route the adult birds lead them on. Others have special chemical compounds in their eyes, bills, or brains that can sense the magnetic fields of the planet to orient themselves. Those birds that migrate at night actually navigate by the stars and constellations, just as ancient sailors did.

In the United States and Canada, millions of birds leave their summer homes and begin their long trip south. Large areas of the U.S. Gulf Coast are designated as bird sanctuaries. In these areas, it is illegal to hunt or kill birds unless it is a specified hunting season. So, even with humans encroaching on their habitats, sanctuaries provide food and rest for the birds as they move to their winter nesting grounds. But where do the birds in other parts of the world go?

The Syrian-African Rift, running 4200 miles from Turkey to Mozambique in Africa, acts like a wind channel, providing a natural flight corridor for birds from Europe and Asia to reach their winter homes. These feathered travelers play important roles in the economics of their countries of origin by distributing seeds of fruit-bearing plants, controlling insects and rodents, and pollinating flowers. By following this overland route, birds don’t have to fly across the Mediterranean, where there is no food or land to rest. Along the way, acting as a land bridge between the Middle East and Africa, lays Israel. There, near a resort town called Eilat, birds have found a refuge after flying across hundreds of miles of desert for up to 40 hours without food, water, or rest.

Where the Roded River empties into the Red Sea, large areas of salt marsh once existed. These marshlands provided nourishment and shelter for hundreds of millions of birds during migration. However, since Israel was established as a nation in 1948, the impetus has been to settle and develop the land for human occupation and use. On paper, nearly a quarter of the land in Israel is set aside as national parkland. In reality, many of these parks constitute less than half a square mile each. As more and more land was developed, areas that birds once used as rest stops could no longer provide for wildlife.

In Eilat, major development for the tourist and agricultural industries eventually converted all of the salt marshes to other uses. So, in 1993, when the International Birding and Research Center in Eilat (IBRCE) obtained an abandoned garbage dump, the organization set out to reclaim the abused land for the birds. Those involved in the restoration of the land faced immense opposition from the local community—not because they were working to restore the land, but because they were doing it for the sake of wildlife, rather than people. As they proceeded, the IBRCE dealt with pressure from locals in the forms of vandalism of equipment, destruction of the research center by arson, and even the killing of a researcher’s dog. Local police failed to pursue any investigation into the incidents. In time, despite all of the obstacles placed in the way, the IRBCE persevered and the Eilat sanctuary was born.

Now the foremost birding spot in the region, the IBRCE sanctuary has become a popular destination for tourists visiting the resort area. During migration times, some 500 million birds that comprise more than 400 species pass through the sanctuary, attracting bird watchers from around the globe.

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Eilat Birding
Sanctuary in the Desert: Protecting Migratory Birds in Israel
Birding in Eilat

Country: IsraelLocation: Israel is located in the Middle East. It is bordered by the Mediterranean Sea, Lebanon, Jordan, and Egypt.

Area: 20,770 sq km (land and water) (slightly larger than New Jersey)

Climate: Israel has a temperate climate. The southern and eastern desert areas are hot and dry.

Terrain: The terrain of Israel includes deserts, mountains, low coastal plains, and valleys.

Natural Resources: Clays, copper ore, magnesium bromite, natural gas, phosphate rock, potash, sand, and timber

Economics: $252.8 billion (est. 2012)

Environmental Issues: Desertification, limited freshwater resources, air pollution, groundwater pollution

Source: CIA – The World Factbook 

Early Birds: Songbird Migration and Climate Change

eastern bluebirds

Research indicates that climate change affects the migration behavior of songbirds. (Photo credit: iStockphoto.com)

The first green seedlings erupt from the cold, brown earth; pink blossoms unfold on tree branches; and insect populations burgeon. As our globe warms, those who live in the northern parts of North America and Europe do not generally complain about the earlier and earlier arrival of spring. But what does an early spring mean to the migratory birds that inhabit those ecosystems? It appears to be changing their rhythms. Over the past half century, abundant data has revealed a picture of changes in bird behavior that corresponds to changes in climate. One thing is clear: migratory birds of North America and Europe are arriving earlier at their northern nesting grounds each year. Some species seem to be adapting to the climate change, while others may be at risk.

Allen Hurlbert and a team of researchers at the University of North Carolina conducted a recent study of bird migration and climate change. Although covering only the past ten years, the dataset used in the study was robust—it consisted of more than 48 million bird observations taken of 18 different species. The data was gathered by about 35,000 citizens as part of a citizen science project called eBird. The website, created by the Cornell Lab of Ornithology and the National Audubon Society in 2002, allows amateur birdwatchers to log into the site and submit their sightings. Experts review any unusual observations. Hurlbert and his team then correlated recorded temperatures with first sightings of bird species at their nesting grounds. They found that birds have shifted their migration on average nearly a day for every degree Celsius the climate has warmed. Some species arrived as many as three to six days early for each rise in degree. Other species adhere to their historic schedules.

According to Hurlbert, the change in birds’ migration patterns could affect the health of bird populations, as the timing of their arrival is critical. Species that arrive early as well as those that maintain their historic migration patterns are both at risk. Birds that arrive at their northern breeding grounds too early may suffer if the threat of severe winter weather has not yet completely passed. Birds that arrive too late may miss the peak in the spring insect populations and be outcompeted by earlier arriving birds.

These and other researchers have found that birds with the longest migration routes may not adapt as quickly to climate change. Those, like the great crested flycatcher, which winters in South America, are the slowest to change. The triggers for migration come from environmental conditions, and the birds in South America have no way of knowing when spring is arriving in the northern United States. On the other hand, birds with shorter migration routes may have an advantage. For example, an early spring in Massachusetts usually coincides with an early spring in North Carolina, so birds wintering there may be receiving early cues that it is time to pack up and head north.

In another study, researchers found that a different flycatcher species, the pied flycatcher, has started migrating earlier in the spring due to climate change, but still reaches its destination on time. The study found that the earlier departure date appears to be related to birth time—that birds born earlier also migrate earlier. However, bad weather in North Africa, which is along the pied flycatcher’s route from West Africa to Europe, slows the birds’ advance and they end up reaching Sweden and The Netherlands at their usual times. This ability to adjust its schedule en-route may turn out to be an advantage for slower migrating species such as the pied flycatcher.

In addition to adjusting departure and arrival dates, several migratory bird species are changing their winter destinations. More than half of over 300 bird species monitored by the Audubon Society have shifted their winter ranges roughly 35 miles farther north from where they were 40 years ago. Again, the researchers point to climate change. The average temperature in January has climbed by nearly 3 °C in the U.S. during that time. The birds are most likely following shifting ranges in available food and nesting sites.

All these studies seem to confirm the same thing: that global climate change is affecting bird migration. The next step that scientists are working toward is understanding the mechanisms behind the changes. More research is needed to determine whether there is flexibility in birds’ inherited migration instincts or if the instincts themselves are changing. In other words, it is not clear whether the changes in migration behaviors are evolutionary responses to the changes in temperature. It is also not known what role a host of other factors play in modulating bird migration, such as wind direction, wind speed, and the condition of the birds themselves.

Finally, researchers would like to have enough information to make predictions about the future of specific bird populations. If temperatures continue to increase, how will migratory birds and other animals adapt or fail to adapt? This information may not only prevent extinctions, but help us understand the bigger picture of how our planet is changing. As indicator species, birds are affected by subtle tweaks in temperature. But ultimately, we all may need to adapt as the climate, and thus the ecosystems around us, change.

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Birds and Climate Change: On the Move
Atlas of Climate Change Effects in 150 Bird Species
Climate Change: In Graphics

Making a Difference: Butterfly Ecologist

Dr. Alfonso Alonso

Dr. Alfonso Alonso examines a monarch as part of his efforts to understand its ecology.

Imagine millions of butterflies swirling through the air like autumn leaves, clinging in tightly packed masses to tree trunks and branches, and covering low-lying forest vegetation like a luxurious, moving carpet. According to butterfly ecologist Alfonso Alonso, this is quite a sight to see.

[Read more…]