Thursday, March 5, 2015

Hurricanes spread lionfish far and wide

Hurricanes moving through the Gulf of Mexico influenced the spread of lionfish.  Whereas the normal flow of the Florida Current would have contained the population of lionfish to the Straits of  Florida, hurricanes disrupted the current and pushed lionfish into the Bahamas.  Between 1992 and 2006, researchers identified 23 instances where hurricanes provided lionfish the opportunity to breach the current. Introduction into the Bahamas, and no longer confined by the Florida Current, spread of lionfish increased by 45% and their population by 15%.

lionfish (Pterois volitans) by Rebekah D. Wallace, University of Georgia,

For more on the study: Hurricanes help spread invasive marine species, researchers find
And: Hurricanes helped accelerate spread of lionfish

Wednesday, March 4, 2015

Citizen Science for the Long View

Widely considered the Father of Phenology, Robert Marsham was very interested in documenting what he would call "The Indicators of Spring."  These are documentations of weather, animal, and plant activities and measurements which he and his descendants collected from 1736 to 1958. Of current interest for scientists studying the effects of climate change on the environment, they recorded the spring leafing and flowering time of the woodland plants on their estate in Norfolk.  This account is one of the longest running phenology records worldwide.

In a recent study, scientists from the University of Edinburgh and Biomathematics & Statistics Scotland used the data gathered by the Marsham family, and weather data gathered from the Central England temperature (CET) record, and evaluated the effect of temperature on fourteen species.  The study found that while all species will leaf and flower sooner after experiencing a warmer spring, a warm autumn will affect some early season leafing trees, such as birch, as compared to the later season leafing trees, like oak.  This effect may be due to certain species' chilling requirements and it is predicted that if seasonal temperatures continue to increase, oak may come into leafing earlier than birch over time.

river birch (Betula nigra) by T. Davis Sydnor, The Ohio State University,

The unfortunate reality is that most data becomes lost or forgotten after the project ends.  Citizen science programs can be very useful in that new people can be continually added to the project and the data collecting can live on through new membership.  Citizen science programs similar to the work that the Marsham family did for so long exist in Project Budburst, Nature's Notebook, the National Phenology Network and many other projects.

For more on the study: Family log of spring's arrival helps predict climate-driven change
For more about Robert Marsham: Robert Marsham and Robert Marsham: The father of springtime records
For more information and a list of Citizen Science Programs: Scientific American - Citizen Science

Tuesday, March 3, 2015

Asian carp on the menu for native fish

bighead carp (Hypophthalmichthys nobilis) by U.S. Geological Survey Archive, U.S. Geological Survey,

Asian carp is a common name for several species of fish introduced from Asia.  The two most concerning of the species are silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis), which were brought to the U.S. in the 1970s for use in aquaculture ponds and water treatment systems.  It is thought that flooding in the 1990s allowed the carp to escape into the Mississippi River system where they are trying to make their way into the Great Lakes.  The primary concern with the introduction of these fish is their voracious appetite for plankton, which is a primary food source for larval fish, native mussels, and some adult fish. Current methods of slowing the spread of Asian carp haven't been entirely successful, as they have been found to move beyond electric barriers meant to exclude them from moving further up the Mississippi River.

However, at the recent Midwest Fish & Wildlife Conference, a presentation by Cory Anderson of Western Illinois University showed that some native fish have begun to prey upon Asian carp.  Not only were the Asian carp being fed upon opportunistically, they were finding that certain species' stomach contents indicated that they were deliberately selecting Asian carp as a food source.  Due to the size of the carp, most of the predation occurred on immatures and small adults.  However, blue catfish is a quite large species and found to have consumed carp as large as 22-40 inches long.  Blue catfish aren't native to the Great Lakes, but there is another large catfish, flathead catfish, which may find room on their plate for Asian carp.

For more on the findings: Asian carp being eaten by native fish, new studies find

Wednesday, February 25, 2015

Not a one-way street: yellow sugarcane aphid native to North America found in Europe

In the U.S. we may often forget that other countries have their own issues with invasive species.  the yellow sugarcane aphid (Sipha flava) was recently found in northeast Spain in two different municipalities, La Selva del Camp (province of Tarragona) and Blanes (province of Girona) and is believed to have come to Spain by way of north Africa.  While surgarcane is not a major crop in Europe, the aphid is known to feed on other species of grasses and it is not known what the impact may be on other important grass crops in Europe, such as rice and corn.

Sipha flava by Kansas Department of Agriculture Archive,

For more information on the find: Yellow Sugarcane Aphid Detected in Continental Europe