Ruffe will leave the deep dark water where they prefer and journey to warmer shallow water for spawning.

** Ruffe, Gymnocephalus cernuus.

The Eurasian Ruffe, also simply Ruffe or Pope ( Gymnocephalus cernuus ) is a freshwater fish found in temperate regions of Europe and northern Asia.

Ruffe eat the young of the signal crayfish which is threatening many European water creatures.

" Ruffe: A New Threat to Our Fisheries.

* Species Profile-Eurasian Ruffe ( Gymnocephalus cernuus ), National Invasive Species Information Center, United States National Agricultural Library.

Lists general information and resources for Eurasian Ruffe.

Many young singers start out as soubrettes but as they grow older and the voice matures more physically they may be reclassified as another voice type, usually either a light lyric soprano, a lyric coloratura soprano, or a coloratura mezzo-soprano.

Most early varieties are very vulnerable ; they should be planted early so that the crop matures before blight starts ( usually in July ).

As a tadpole matures, it most commonly metamorphosizes by gradually growing limbs ( usually the legs first, followed by the arms ) and then ( most commonly in the case of frogs ) outwardly absorbing its tail by apoptosis.

The fruit matures to a capsule, 2 – 5 cm diameter, usually globose, containing 1-3 seeds ( often erroneously called a nut ) per capsule.

The male swift fox matures and may mate at one, while the female usually waits until her second year before breeding.

Small patches of demodicosis often correct themselves over time as the dog's immune system matures, although treatment is usually recommended.

Swamp laurel oak grows rapidly and usually matures in about 50 years which has led to its wide use as an ornamental.

A medium-term note ( MTN ) is a debt note that usually matures ( is paid back ) in 5 – 10 years, but the term may be less than one year or as long as 50 years.

( For the etrog, this means that the stem end should be on the bottom and the blossom end on top ; this is the direction in which the etrog begins to grow, though as it matures on the tree it usually hangs in the opposite direction.

Shows which are performed once or only a few times are often not considered candidates for show control since considerable preplanning and programming is usually required, but this may change as the technology, ease of operation and programming of show control software and systems matures.

They may even enroll a colored student or two for show, though he usually turns out to be from Thailand, or any place other than the American South.

So all-important are ideas, we are told, that persons successful in business and happy in social life usually fall into two classes: those who invent new ideas of their own, and those who borrow, beg, or steal from others.

On Sundays, with the permission of Captain Heard, who usually attended with two of his officers, services were held in the double cabin.

So the Commission's announcements of the new Soviet shots have been confined to one or two bleak sentences, with the fission yield usually left vague.

About a quarter of Hardy's poems carry an appended date line, usually the year of completion, but sometimes inclusive years ( `` 1908 - 1910 '' ) or two separate dates when Hardy worked on the poem ( `` 1905 and 1926 '' ) or an approximate date ( `` During the War '' ).

`` After your child's baby teeth are all in -- usually at the age of two and one half to three -- it's time for that first dental appointment '', Dr. Brodie advises.

If you are not well acquainted with the area in which you wish to locate, or if you are not sure that you and your family will like and make a success of farming, usually you would do better to rent a place for a year or two before you buy.

Even a city of thirty thousand might have six baseball teams, sponsored by grocers and hardware merchants or department stores, that played two or three times a week throughout the summer, usually in the cool of the evening, before an earnest and partisan audience who did not begrudge a quarter each, or even more, to be dropped into a hat when the game was half over.

The education bill appears to be temporarily stalled in the Rules Committee, where two Northern Democratic members who usually vote with the Administration are balking because of the religious controversy.

But when Gloriana rides with them they also have to take the two girls who usually ride with her, so the little car isn't big enough.

The liver is usually large with two lobes.

Holders of territories have a " home advantage " and usually come off better in an encounter between two similar sized frogs.

The wires are usually bowed to bulge upward in the center, to keep the beads pinned to either of the two sides.

Adobe walls usually never rise above two stories because they are load bearing and have low structural strength.

The three petals ( or inner tepals ), also showy, are located alternately between the sepals, two at the side and one usually at the bottom of the flower.

The two large families are cosmopolitan, with many of their species found in the northern hemisphere, and the smaller families are usually confined to Australia and the adjacent areas, or sometimes South America.

The experience requirement for degreed candidates is usually satisfied by a practicum or internship ( usually two to three years, depending on jurisdiction ).

During each winter there is usually one fall of snow in the south and two in the north ; but the snow quickly disappears, and sometimes, during an entire winter, the ground is not covered with snow.

Arminian theology usually falls into one of two groups — Classical Arminianism, drawn from the teaching of Jacobus Arminius — and Wesleyan Arminian, drawing primarily from Wesley.

The two terms may not have originally been distinguished ; though in Homer's poems nectar is usually the drink and ambrosia the food of the gods ; it was with ambrosia Hera " cleansed all defilement from her lovely flesh ", and with ambrosia Athena prepared Penelope in her sleep, so that when she appeared for the final time before her suitors, the effects of years had been stripped away and they were inflamed with passion at the sight of her.

" Identical vertices " are usually taken to mean that for any two vertices, there must be an isometry of the entire solid that takes one vertex to the other.

In addition to over, Porter and Duff defined the compositing operators in, held out by ( usually abbreviated out ), atop, and xor ( and the reverse operators rover, rin, rout, and ratop ) from a consideration of choices in blending the colors of two pixels when their coverage is, conceptually, overlaid orthogonally:

In three dimensions, a single equation usually gives a surface, and a curve must be specified as the intersection of two surfaces ( see below ), or as a system of parametric equations.

The same types of conditions are usually considered stressful for these two types of organisms.