Nature Word of the Week: Cere

This week's Nature Word - cere - was pulled from the avian morphology category.

The cere on this Peregrine Falcon is yellow.

Cere is defined in two ways by thefreedictionary.com  (see link for pronunciation):

• To wrap in or as if in cerecloth (cerecloth being  a type of waxed cloth used for wrapping a corpse)
•  A fleshy or waxlike membrane at the base of the upper beak in certain birds, such as parrots, through which the nostrils open.

So the cere is as plain as the nose on a bird's beak.  Or at least on "certain birds" which have ceres, such as raptors, owls, skuas, parrots, turkeys and curassows.

The cere can be feathered, but is more commonly bare, and it is often brightly colored.  According to Wikipedia, the cere in raptors "is a sexual signal which indicates the "quality" of a bird".  (Makes you want to look a little more closely at the Raptor Cam, doesn't it?)  Also, the cere can be a good field mark, helpful in distinguishing between the sexes of some species.

The cere should not be confused with the operculum, which is more of a cover for the nares (or nostrils) of some birds.

Nature Word of the Week: Accidental

This week's Nature Word is: Accidental

We all know the meaning of accidental in every day speech, so we probably have a good idea of what it would mean when used to describe species occurrence.  But let's take a closer look at this and other words used to talk about how often a particular species is seen in a given area.  (These words are most commonly used in reference to bird species, but they could also apply to any highly-mobile group of animals.)

Image credit: University of Columbia, SECAC, NASA, via Wikipedia

Merriam-Webster lists three definitions for accidental, but the one that fits best, when describing species occurrence is this: 

occurring unexpectedly or by chance

The National Audubon Society Field Guide to North American Birds (Western Region, second edition, August 2000) defines accidental as:

A species that has appeared in a given area only a very few times and whose normal range is in another area.

Accidental species then, probably took a wrong turn at Albuquerque.


At the opposite end of the occurrence scale, we have the term permanent resident.  This, of course, is self-explanatory - it describes an animal species that lives in the area all year round.  You could also have a winter or summer resident if the species is migratory (moving between a winter range and a summer range). 

Somewhere in the middle of the scale, we have a couple of different terms:

• Casual - A species that has appeared in a given area somewhat more frequently than an accidental, but whose normal range is in another area.  (The National Audubon Society Field Guide to North American Birds Western Region, second edition, August 2000)
•  Erratic - Occurring in numbers some years, but very scarce or even absent in others.  (US Fish and Wildlife Service)

You could also use erratic in conjunction with migration, to describe an erratic migrant - a species that moves through an area in some years but not others.

Related to species occurrence, we have a whole list of terms which describe species distribution or range (Definitions below from The National Audubon Society Field Guide to North American Birds Western Region, second edition, August 2000):

•  Circumpolar - Of or inhabiting the Arctic (or Antarctic) regions in both the Eastern and Western hemispheres.
• Cosmopolitan - Worldwide in distribution, or at least occurring in all continents except Antarctica.
• Equatorial - Of or inhabiting the equatorial regions.
• Local - Occurring in relatively small, restricted areas within the range, rather than commonly and widespread throughout the range.  (Species whose occurrence is local usually have highly specialized habitat requirements.)
• Pelagic - Of or inhabiting the open ocean.
• Riparian - Of or inhabiting the banks of rivers or streams.
• Subalpine - Of or inhabiting/pertaining to the stunted forest or other vegetation immediately below the treeless, barren alpine zone on high mountains.
• Woodland, coastal, etc.,

Nature Word of the Week: Pinnate

This is the first posting of a new weekly feature... Nature Word of the Week.  Every Wednesday, I'll define a different nature-related word.  I'll try to mix it up, referencing different sources and choosing words of varying obscurity or technical level.  Probably nothing new for the professional scientist-types out there, but hopefully interesting or even instructive for casual nature observers like me.  I know I'll be learning as I create these posts.

So without further ado (OK, maybe just a little trumpet fanfare), the Nature of Portland proudly presents the very first, Nature Word of the Week!

This Week's Nature Word is: Pinnate

From Wiktionary.org:

1. Resembling a feather.
2. (botany) Having two rows of branches, lobes, leaflets, or veins arranged on each side of a common axis
   

Pinnate leaves on a palm tree in the Phoenix genus - credit: Mmcknight4 via Wiktionary

From Wikipedia.org:

Botanically, the term describes an arrangement of discrete structures (such as leaflets, veins, lobes, branches, or appendages) arising at multiple points along a common axis. For example, once-divided leaf blades having leaflets arranged on both sides of a rachis are pinnately compound leaves. Many palms (notably the feather palms) and most cycads and grevilleas have pinnately divided leaves. Most species of ferns have pinnate or more highly divided fronds, and in ferns the leaflets or segments are typically referred to as "pinnae" (singular "pinna"). Plants with pinnate leaves are sometimes colloquially called "feather-leaved".

pinnatifid and pinnatipartite: leaves with pinnate lobes that are not discrete, remaining sufficiently connected to each other that they are not separate leaflets.
pinnatisect: cut all the way to the midrib or other axis, but with the bases of the pinnae not contracted to form discrete leaflets.
pinnate-pinnatifid: pinnate, with the pinnae being pinnatifid.
paripinnate: pinnately-compound leaves in which leaflets are born in pairs along the rachis without a single terminal leaflet; also called "even-pinnate".
imparipinnate: pinnately-compound leaves in which there is a lone terminal leaflet rather than a terminal pair of leaflets; also called "odd-pinnate".
bipinnate: pinnately compound leaves in which the leaflets are themselves pinnately-compound; also called "twice-pinnate".
tripinnate: pinnately compound leaves in which the leaflets are themselves bipinnate; also called "thrice-pinnate".
tetrapinnate: pinnately compound leaves in which the leaflets are themselves tripinnate.

A pinnate frond of the fern, Blechnum appendiculatum - credit: Marshman via Wikipedia