Loose Feathers #358

Palm Warbler / Photo by Keenan Adams (USFWS)

Birds and birding

• Fossils discovered in China provide an example of therapods eating prehistoric birds and small feathered dinosaurs.
• Scientists are trying to find out if Blue Tits might be able to control an invasive moth in the UK.
• Climate change may increase the spread of avian influenza in wild birds by disrupting their normal migration patterns. 
• The breeding population of Chinstrap Penguins is declining on the Antarctic Peninsula. The researchers think that climate change is the most likely culprit.
• This video shows a Green Heron using a piece of bread as bait to catch a fish.
• A series of images show a Velvet-purple Coronet and a Buff-tailed Coronet fighting over the right to feed at a banana flower.
• Ecologists are pushing the French government to stop unregulated hunting on the island of Guadeloupe.

Nature blogging

• Net Results: Dearborn Passenger Pigeons: Then and Now
• 10,000 Birds: How do Birds get their Color?
• Birding Frontiers: Jankowski’s Bunting: A Very Rare Bird Indeed
• The Smaller Majority: Danger, in black and white
• Bug Eric: Wasp Wednesday: Ageniella accepta/conflicta
• BugBlog: On insect migration and fairy tales
• Nemesis Bird: Maryland Herald Petrel – 8/25/12
• Laelaps: Giant Squid vs. Mosasaur
• Not Exactly Rocket Science: Robins start with a magnetic compass in both eyes, and end up with just one 
• PetaPixel: Hiker in Alaska Killed After Taking Close-Up Pictures of a Grizzly Bear

Environment and biodiversity

• Scientists finally figured out what a strange-looking marine larva becomes as an adult.
• A recent study showed how the extinction of one species can hurt other species.
• A botany study proved that New England Banksia is a separate species from Hairpin Banksia.
• Three prehistoric arthropods — a midge and two mites — have been found in Triassic amber from Italy.
• Sea ice in the Arctic is already at a record low. With three weeks of melting left, this summer will likely break the record by a substantial margin.
• Shad have virtually disappeared from the Delaware River, and attempts to restore them have had frustratingly slow results.
• Yosemite National Park has closed 91 cabins after two people died from hantavirus after sleeping there.
• A man was caught trying to enter Switzerland with 15 kilograms of caterpillars in a false compartment in his luggage. When he was caught, he started eating them.
• Climate change may cause significant changes to the stretches of the Atlantic coastline within the National Park system from erosion and rising temperatures. 
• The Obama administration has given Shell permission to start preparations for drilling in the Chukchi Sea.
• An unidentified white moth from Venezuela has become a hit on social media sites.
• Five new species of cuckoo bees were documented on the Cape Verde Islands.

Grass Diversity

Recently someone asked me questions about particular grasses, and I realized I could not answer them because I knew next to nothing about grasses. I mean, I can recognize certain grasses like the ubiquitous Phragmites australis and a few other wetland grasses like cattails and Spartina. Beyond those, though, my knowledge is very limited. So I have been making an effort to learn more about the grasses I encounter in the types of habitats I bird frequently.

Grasses (family Poaceae) are an incredibly important group. Wheat, oats, barley, rye, corn, and rice are all grasses, as is bamboo. Many species of butterflies and moths, such as skippers and grass-veneers, use grasses as their larval host plants. Some bird species also associate with particular grasses or depend on habitats where grasses predominate. Along with grasses, rushes (family Juncaceae) and sedges (family Cyperaceae) may be found in those sorts of habitats and present similar identification challenges. Grasses, sedges, and rushes are all in the order Poales, along with many other plant families.

One of the distinctive native grasses is wild rice, a plant of wetland habitats. The wild rice sold commercially is usually Zizania palustris, a species native to the Great Lakes region. In my area, the native wild rice is Zizania aquatica. Wild rice is an important food source for waterfowl and other wetland birds. A distinctive feature of wild rice is that the male and female flowers are on separate branches. The female flowers are on thin branches that stick up from the top of the stem; male flowers droop from horizontal branches below the female flowers. The photo above shows the male flowers on one plant.

Another wetland grass is cockspur (Echinochloa sp.). Plants in this genus are sometimes grown as forage crops for livestock, but otherwise just grow wild. I think this is E. walteri, a grass of both saltwater and freshwater marshes that characteristically long bristles along its spikelets.

Like grasses, rushes have round stems, but their flowers and seeds are structured somewhat differently. On this Soft Rush (Juncus effusus), the flowers burst in a clump from the side of the stem rather than emerging from the top.

Sedges are another group of plants that grow in wetlands and meadows. As a group, sedges are fairly easy to recognize because most of them have obviously triangular stems ("sedges have edges"). Narrowing down to a species, though, can be more difficult. I think the plant above is a Dark Green Bulrush (Scirpus atrovirens), which shows one common sedge structure. The main stem ends in a leafy bract, from which several branches emerge that bear the sedge's flowers. Another plant that shares a similar structure is Yellow Nutsedge.

So far I have been aided in my learning by Grasses: An Identification Guide by Lauren Brown. This guide, published by Houghton Mifflin, uses simplified terminology and emphasizes broad characteristics such as shape and color rather than minute details. (The latter, unfortunately, may still be necessary to confirm a species identification.) The book contains a key followed by descriptions of 135 species from the Midwest and Northeast. I have found it very helpful as an entry point to learning about grasses.

Loose Feathers #357

Puerto Rican Nightjar / Photo by Mike Morel (USFWS)

Birds and birding

• EBird has finished its latest taxonomic update. Here's an explanation of the changes.
• Male Rock Sparrows vary their songs based on their reproductive success; in particular, male sparrows react to their mates' infidelity by singing more loudly.
• Seabird colonies have an under-researched impact of the global environment through their impressive ammonia production (via guano). Recent research concluded that seabirds produce 404 Gigagrams of ammonia each year — about 2% of global ammonia production. Penguins account for 80% of this total.
• Speaking of seabirds, Scotland's kittiwake colonies are undergoing severe declines.
• Use of native plants in landscaping can be helpful for birds living in urban settings.
• Squirrels do not just empty seed from bird feeders; they also chew into zoo enclosures and let the caged birds out.
• The American Bird Conservancy has produced a 30-minute film on the ongoing extinction crisis in Hawai'i.
• A new bird species, the Antioquia Wren (Thryophilus sernai), was discovered in Colombia along the Cauca River. Unfortunately its habitat is threatened by mining and deforestation since none of it is protected. 
• Two new owl species were discovered in the Philippines, Camiguin Hawk-owl (Ninox leventisi) and Cebu Hawk-owl (Ninox rumseyi).
• Xeno-Canto has a feature article on Rufous Antpitta vocalizations.
• Here are some photos of critically endangered Blue-throated Macaws.

Nature blogging

• Laelaps: Unless They’re Zombies, Fossils Don’t Live
• March of the Fossil Penguins: Brain in Hand
• The Smaller Majority: The holotype that walked away 
• Sibley Guides: Identification of Waterthrushes 

Environment and biodiversity

• Much has been written about how climate change will harm some parts of the world more than others. A recent analysis shows that such variation exists even within a single state. 
• As climate change progresses, many cities will need to make decisions about how to cope with these changes, such as rising sea levels. Olympia, Washington, is considering whether to build a new sea wall or gradually abandon part of its city center, which was built on fill.
• Using data from butterfly counts conducted by the Massachusetts Butterfly Club, a new study found that climate change is causing butterfly species to shift their ranges northward. Two species that have shown exceptional increases are Giant Swallowtail and Zabulon Skipper. Meanwhile Atlantis and Aphrodite Fritillaries are rapidly decreasing.
• According to a new report, up to 40% of food in the United States is wasted, and up to 25% of the food that Americans buy goes to waste. Here is the full report from the NRDC. One of the more discouraging statistics for conservationists is that 50% of seafood goes to waste when many fish stocks are in severe decline due to overfishing.
• A new spider species called Trogloraptor has been found in the caves of southern Oregon. Trogloraptor is 4cm long and sports curved claws at the ends of its legs. The species is so novel that naming it required the creation of a new spider family.
• Political events this week revealed that a prominent member of the House Science, Space, and Technology Committee is profoundly misinformed about science, a problem that seem to be widespread among members of that committee, with disturbing implications for both wildlife conservation and mitigating climate change.
• In better news, Madagascar protected 1,438 square miles of rainforest as Makira Natural Park. The new park is home to numerous rare and endangered wildlife species.
• A newly-discovered rat species has only incisors for teeth, with no molars to back them up. This is highly unusual for a rodent species and indicates that it probably eats a soft diet.
• Two new species of forget-me-nots have been found in New Zealand.
• Yao Ming is filming a documentary meant to persuade Chinese residents to stop using elephant ivory and rhinoceros horn.
• Some scientists are investigating a new dispersant formula made from edible ingredients that would break up oil slicks and keep oil from sticking to birds' feathers but would be less harmful than current dispersants. I am skeptical of this working and being implemented on a large scale, but I see any research towards less unhealthy oil dispersants as a positive step.
• Most states do not require energy companies to tell residents if they are fracking nearby.
• In some English cemeteries, groundskeepers are trying to develop a more natural landscape that includes wildflowers and other native plants.

Herons at De Korte Park

Yesterday I was at De Korte Park in the Meadowlands. There had been a number of interesting sightings there in the past few weeks, and I was eager to track down a few of them. The first, Least Bittern, was in its usual spot at the start of the Marsh Discovery Trail. Least Bitterns bred here over the summer, and for the past few weeks, the juveniles have been coming out of the reeds and sitting in the open. The bitterns were really hard to see yesterday, perhaps owing to the high water level. One briefly came out of the reeds, and another perched just inside the reeds on the other side of the island. Initially I mistook the second one for a rail, but it turned out to be a second Least Bittern juvenile after further examination. Neither was in a good clear position for me to photograph them. It was delightful to see them, especially since I had not seen one in five years, and it was my first sighting of one in New Jersey.

A second bird I was interested in seeing was a Tricolored Heron. This immature heron was foraging at the far end of the East Shorebird Pool, almost all the way to the NJ Turnpike. There are also quite a lot of Great Egrets and Snowy Egrets patrolling the edges of the pools.

As I mentioned, the water levels are higher than ideal, which means in turn that shorebird numbers are pretty low. However, there are still about 500 Semipalmated Sandpipers in the Shorebird Pools, along with a few dozen yellowlegs. I noted on Short-billed Dowitcher and one Spotted Sandpiper in addition to those birds.

Donaldson Dragonflies

Recently I started participating in the Dragonfly Pond Watch Project run by the Migratory Dragonfly Partnership. I hear about a lot of projects like this through insect bloggers; in this case I heard about it through the Xerces Society's newsletter. This particular project tracks the migratory movements of two very common dragonflies, the Common Green Darner (Anax junius) and Black Saddlebags (Tramea lacerata). It involves periodically counting dragonflies at the same pond over the course of the fall migration period. This works well for me since an artificial pond is part of my normal walking route through my local patch, and I can just add 15 or 20 minutes to my normal route to count dragonflies there.

So far the results have not been auspicious. My first visit, on August 2, netted exactly one Black Saddlebags and no Common Green Darners. During my second visit to the pond yesterday, I saw neither of the target species during my count period. Most of the odonate activity around the pond consisted of Eastern Amberwings and Familiar Bluets, with an Eastern Forktail thrown in for good measure. One red dragonfly caught my eye, so I photographed it as best I could. After reviewing my dragonfly resources, I think this is a male Needham's Skimmer. The lack of black triangles along the sides of the abdomen rule out most meadowhawks. The closest species in appearance is the Golden-winged Skimmer, which is more uncommon in this state than Needham's Skimmer, especially on the coastal plain. Plus there are hints of a few other features characteristic of Needham's but not Golden-winged.

I mentioned in the previous paragraph that I did not see either of my target species during the count. Of course, when I walked along the river to continue my route, what do I see on the other side of the field? Black Saddlebags. And not just one, but a half-dozen or more. In their company was a Common Green Darner. If I did my watch by the basketball courts instead of at the pond, I would be recording more sightings.