Uldis Roze

• Ph. D.
• Professor Emeritus at Queens College, CUNY

Scanning electron microscopy shows that the quill surface from the thin-spined porcupine (Chaetomys subspinosus (Olfers, 1818)) has several regional cuticular patterns of which the most expansive is highly pitted with 4 μm wide pores leading to pits, which in turn communicate circumferentially via tunnels to neighboring pits. The cell unit of the p...

Could a porcupine make a good pet? Do they ever stick themselves or other porcupines with their quills? In this latest addition to the Animal Answer Guide series, we learn about these mysterious animals' "pincushion defense" along with the following facts: porcupines survive on a diet of leaves, bark, and fruit quills are actually modified hairs th...

Winter feeding of individual porcupines (Erethizon dorsatum L.) was studied in the northern Catskill Mountains of New York by following individual feeding trails in the snow. The study population as a whole fed primarily on beech (Fagus grandifolia) and sugar maple (Acer saccharum) and less frequently on eight other tree species. Individual porcupi...

Long-term radiotelemetry was used to study patterns of den use and winter movement in porcupines (Erethizon dorsatum) in New York. Six of eight animals used dens regularly; the rest spent most of their winters in the shelter of hemlock stands (Tsuga canadensis). Animals entered dens in October–November after minimum daily temperatures had fallen be...

The perineal glands of the porcupine, Erethizon dorsatum (L., 1758), are sexually dimorphic, paired pockets sprouting osmetrichial hairs. They lie between the anus and urethra, lateral to the midline, amid a sebaceous glandular expanse. In their active state, the glandular pockets secrete an amber substance with a terpenoid odor. When inactive, the...

With an arsenal of quills and chemicals, the porcupine mounts one of nature's most robust defenses against predators.

Quill-withdrawal experiments confirm a hypothesis proposing that North American porcupines (Erethizon dorsatum) give up a quill more easily if the quill's root is first thrust back sharply into the porcupine's skin. The hypothesis was tested in 8 porcupines. When quills are impacted in a way that mimics contact with a predator, the tension required...

We evaluated capture methods, marking techniques, and radiocollar design for 50 adult (≥1.0 years old) North American porcupines (Erethizon dorsatum) captured 84 times in Massachusetts during June 1991-July 1993. Of 4 capture methods used, cage traps seemed the safest and most efficient, but we recommend using a combination of capture techniques wh...

Volatile compounds in the lipid coating of the lower-back quills of the North American porcupine,Erethizon dorsatum, were collected using headspace trapping on Tenax and analyzed by gas chromatography–mass spectrometry (GC-MS), GC with organoleptic detection, and GC with a chiral stationary phase. Over 50 components were isolated, primarily oxygena...

The histology of the porcupine's skin and subcutis is described. The functional relationships of the thoracic skin during elevation of the quills involve a smooth arrector muscle attached to quill sets, one set behind the other, with the muscle at a slant usually from a single root tip of one set to the distal part of the follicles in the caudal se...

Porcupine quills possess antibiotic properties. The antibiotic activity is associated with free fatty acids (but not neutral lipids) coating the quills. Extracts of quill fatty acids strongly inhibited the growth of six grampositive bacterial strains. No growth inhibition was observed against four gram-negative strains. Free fatty acids made up 18....