Population Trend
Definition
Population trend describes whether a species is increasing, stable, decreasing, or unknown over a defined time period, typically three generations. Tracking population trends is essential for penguin conservation because it reveals whether threats are being managed effectively. Several penguin species show alarming declines: the African penguin has lost over 95% of its population since the early 1900s, while Galapagos penguin numbers have dropped roughly 75% since the 1970s. Satellite imagery and ground counts at breeding colonies are the primary methods for estimating penguin population trends.
Related Terms
The IUCN Red List of Threatened Species is the world's most comprehensive inventory of the conservation status of plant and animal species, maintained by the International Union for Conservation of Nature.
Endangered is an IUCN Red List category indicating a species faces a very high risk of extinction in the wild.
A penguin colony (also called a rookery) is a breeding aggregation that can range from a few dozen pairs to over a million individuals.
Related Species
Species where population trend is especially relevant.
Frequently Asked Questions
What does population trend mean in penguin biology?
Population trend describes whether a species is increasing, stable, decreasing, or unknown over a defined time period, typically three generations. Tracking population trends is essential for penguin conservation because it reveals whether threats are being managed effectively. Several penguin species show alarming declines: the African penguin has lost over 95% of its population since the early 1900s, while Galapagos penguin numbers have dropped roughly 75% since the 1970s. Satellite imagery and ground counts at breeding colonies are the primary methods for estimating penguin population trends.
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Glossary entries define the language. FAQ answers common questions; guides carry the longer Survival Lab arguments.
More in conservationWhere this definition comes from
Reference bodies behind the conservation terminology. Links last checked August 5, 2026.
- IUCN Red List - Global conservation assessments and extinction-risk categories.
- BirdLife Data Zone - Species accounts, distribution, and population summaries.
- SANCCOB - African penguin rescue, rehabilitation, and conservation context.