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Agents of Deterioration That Threaten Collection Specimens


  • School buses parked too close to a gas regulator.

    Robert Waller © Canadian Museum of Nature


    Outside this former museum building, the risk of physical damage to the natural gas regulator, and therefore, the risk of fire, is evident.

  • Wild bergamot, Monarda fistulosa CAN16785.

    Barbara Njie © Canadian Museum of Nature


    Water marks on this Herbarium sheet represent damage caused by flooding. This specimen of wild bergamot was collected by John Macoun on July 18, 1878.

  • Covellite NMC30040.

    George Robinson © Canadian Museum of Nature


    The fuzzy growth of other copper-sulfide phases, digenite and/or djurleite, has altered this covellite specimen. The contamination is thought to result from interaction with hydrogen sulfide emitted from other mineral specimens.

  • Northern leopard frogs, Lithobates pipiens NMC30743.

    Anne Botman © Canadian Museum of Nature

    Light and Ultraviolet Light

    Placed in a south window for eight months, two of the northern leopard frogs in this experiment have faded about as much as they would after several decades of exposure under controlled lighting conditions in an exhibition. The colour of the centre frog is not as faded as that of the frog on the right because it was protected by an ultraviolet light filter. The frog on the left was completely covered by aluminum foil. A belt of aluminum foil was also wrapped around the middle of each; when removed, their original colour is obvious.

  • Sea lampreys, Petromyzon marinus NMC84-0036.

    Martin Lipman © Canadian Museum of Nature

    Physical Forces

    This one-gallon jar is too small for these six sea lamprey specimens. Crowding may cause permanent physical damage to the specimens.

  • Damaged shipping package.

    Robert Waller © Canadian Museum of Nature


    The shipping package is torn open, and the mineral sample is missing.

  • Gentian, Gentiana. Herbarium sheet with damaged gentian flowers.

    Photo: Barbara Njie © Canadian Museum of Nature


    Hungry beetles have damaged the gentian flowers on this Herbarium sheet.

  • Quartz CMN51364.

    Robert Waller © Canadian Museum of Nature

    Incorrect Temperature

    This photograph shows bubbles captured in a quartz specimen. The bubbles contain some of the solution in which this quartz mineral grew. The liquid and gas inclusions were sealed at the pressure under which the mineral formed, typically hundreds or thousands of times greater than that on the Earth's surface. A rise in temperature raised the internal pressure of the inclusions, resulting in the explosion of one of them.

  • Fish larvae stored in jar with low fluid level.

    Photo: Robert Waller © Canadian Museum of Nature / Musée canadien de la nature

    Incorrect Relative Humidity

    Low levels of preservative fluid are a great risk to collections. The museum has 400,000 containers of fluid preservative with a combined container-lid joint length of 100 km. Even slight imperfections in closures become serious problems for fluid-preserved collections. Coincidentally, the label of this jar notes that these fish larvae were found in "shallow water".

  • Jumble of labels and specimens.

    Robert Waller © Canadian Museum of Nature

    Custodial Neglect

    "Pick a label, any label". Losing the connection between specimens and data is a serious risk to any collection. These are whale bones.

  • A mounted beaver specimen showing damage on its skin.

    Luci Cipera © Canadian Museum of Nature

    Incorrect Relative Humidity

    The face and hands of this beaver cracked and split while on display in the museum because of poor humidity control. Taxidermy specimens are very sensitive to changes in relative humidity. Low humidity—such as what we typically experience during our Canadian winters—can cause the taxidermy skin to dehydrate, shrink and split. Prior to the renovation of the museum in 2010, it was difficult to control the humidity. The beaver was repaired and installed in the Mammal Gallery.