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In a new study, researchers at Oregon State University sought to quantify the role bears in Alaska play in dispersing seeds. The authors estimated that brown and black bears disperse over 200,000 seeds per hour per square km while foraging for fleshy fruits and then excreting them on the landscape. Brown bears disperse more seeds than black bears overall, and at different times of the year. Because bears disperse a large percentage of the seeds of fleshy-fruit bearing species, they have a great influence on the species composition of plants in their ecosystems. If populations of bears are reduced, the number of fleshy-fruited shrubs may also decline and be replaced by wind-dispersed plants.

In most of the last ten years, the First Leaf Index has arrived days to weeks earlier than calendar spring in the Washington, DC area. This year, spring leaf out arrived 25 days earlier than the Spring Equinox in Washington, DC.

To better link phenology data from time-lapse cameras and on-the-ground observations, authors of a new study in Ecosphere compared digital images of tree foliage color from spring to autumn to observations made using the USA-NPN protocols. The authors also found that chill and minimum temperature in autumn, drought stress in autumn, and heat stress in summer are all important factors to the timing of peak fall foliage color.

Punxsutawney Phil predicts six more weeks of winter. We agree - if we're talking about the eastern US. The southeast especially has been cool so far this year.  In the west, we are already seeing signs of early spring from trout to snowberries. A new forecast by collaborator Toby Ault also calls for a early spring in the west, late in the east. 

By Groundhog day in 2017, spring had arrived 3-4 weeks early across much of the Southeast. This year, it looks like we will not see a very early spring in the Southeast. However, we predict that by Groundhog day this year, spring will have spread even further into Southwest states this year than last.

Mistletoes, a group of parasitic plants comprising over 1,500 species, have intricate relationships with different host species, pollinators, and seed dispersers to carry out their life cycle. The authors from a new study in Oecologia used data from the USA-NPN’s National Phenology Database from Arizona and California to look for consistencies in the leafing, flowering, and fruiting phenology between desert mistletoe and their host plants. The authors found that mistletoes are not constrained by their hosts when it comes to phenology, and use diverse strategies to maintain reproductive success.

Authors of a new study published in Nature Ecology & Evolution analyzed data from three sources – Henry David Thoreau’s observations recorded over 150 years ago in Massachusetts, four decades of observations collected at the Rocky Mountain Biological Laboratory, and recent observations contributed by Nature’s Notebook participants across the U.S. – to demonstrate how these disparate data sources can be combined to detect changes in flowering phenology over time. The authors found increasing variability in the timing of flowering in recent years across datasets. This suggests that plants may be reaching the limit of how much they can advance their flowering to keep up with changing climate conditions.

The authors of this study used data from two continental-scale observation networks to explore the relationship between migratory birds and environmental cues - observations of migratory birds submitted to eBird and weather surveillance radar, which can detect large groups of migrating birds. They compared the observation data to measurements of vegetation green-up collected via satellites and the USA-NPN’s Spring Leaf Index. The Spring Leaf Index was strongly related to both the estimates of bird species richness from eBird observations and migration intensity collected via weather radar. By better understanding how birds and the habitat on which they rely are responding to climate change, managers will be more equipped to take actions to promote and conserve habitat where it is needed.

While many studies have investigated the relationship between climatic drivers and phenology of plants in temperate areas, few studies have explored these drivers in water-limited ecosystems. Authors from the USA National Phenology Network and the University of California Santa Barbara used observations from Nature’s Notebook to examine how the phenology of two western North American oak species and two eastern and central North American oak species respond to variation in temperature, precipitation, latitude, longitude and elevation. The way that species respond to certain climatic drivers, such as winter precipitation or spring minimum temperatures, can be used to predict how these species will be impacted by climate change.

As of April 24, 2017, the National Phenology Database has reached 10 million records! Each record is a response to a question about phenology activity for a particular plant or animal species on a unique day and time, by a unique observer.

Read more about this milestone in this story in UA News.  

Find out what 10 million records means: