What is the Difference Between Primary Secondary and Tertiary Consumers

The main difference between primary secondary and tertiary consumers is that primary consumers are the herbivores that feed on plants, and secondary consumers can be either carnivores, which prey on other animals, or omnivores, which feed on both animals and plants, whereas tertiary consumers are the apex predators that feed on both secondary and primary consumers. Rabbits, consuming grass are an example of primary consumers; snakes, consuming rabbits are an example of secondary consumers while owls, consuming snakes are an example of tertiary consumers.  

Primary, secondary, and tertiary consumers are the three levels of consumers in an ecological food chain.  

Key Areas Covered 

1. What are Primary Consumers
     – Definition, Characteristics, Examples
2. What are Secondary Consumers
     – Definition, Characteristics, Examples
3. What are Tertiary Consumers
     – Definition, Characteristics, Examples
4. What are the Similarities Between Primary Secondary and Tertiary Consumers
     – Outline of Common Features
5. What is the Difference Between Primary Secondary and Tertiary Consumers
     – Comparison of Key Differences

Key Terms 

Food Chain, Primary Consumers, Primary Producers, Secondary Consumers, Tertiary Consumers 

What are Primary Consumers 

Primary consumers are the animals that feed on primary producers. Moreover, they make the second tropical level of the energy pyramid and are consumed by secondary and tertiary consumers. Furthermore, as they feed on primary producers, which are the autotrophic plants, primary consumers are herbivores. Autotrophs fix energy by photosynthesis.

Figure 1: Deer Feeding on Foliage

Primary consumers have effective mechanisms for the breakdown of carbohydrates. Carbohydrates are the simple organic compounds produced during the fixation of energy by photosynthesis. In addition, they have rows of flat, wide teeth to rasp, tear, and grind plant materials. Moreover, they have symbiotic bacteria in their gut to digest plant material. Ruminants, herbivorous birds, zooplankton, etc. are some examples of primary consumers. 

What are Secondary Consumers 

Secondary consumers are animals that feed on primary consumers. They also make the third tropical level of the energy pyramid. However, they are consumed by tertiary consumers. Secondary consumers can be either carnivores or omnivores. That means; carnivores feed only on primary consumers. But, omnivores feed on both primary consumers and primary producers.

Figure 2: Energy Pyramid

Furthermore, secondary consumers inhabit all types of habitats as they have a vast amount of food sources available. Also, they widely range in size and shape. Some examples of carnivorous secondary consumers are snakes, spiders, and seals. On the other hand, some examples of omnivorous secondary consumers are humans, bears, skunks, etc.  

What are Tertiary Consumers 

Tertiary consumers are animals that feed on both secondary and primary consumers. Generally, they are the apex predators that make the top tropical level of the energy pyramid. Furthermore, the animals on the higher trophic levels play an important role in controlling the population of the animals in the lower trophic levels.

Figure 3: Tertiary Consumers

Moreover, tertiary consumers have the lowest amount of biomass among all other trophic levels. Some examples of marine tertiary consumers are the predatory fish such as pike, great white shark, tiger shark, jellyfish, etc. On the other hand, the big cats including tigers, lions, jaguars, pumas, etc. are the tertiary consumers on the land.  

Similarities Between Primary Secondary and Tertiary Consumers 

• Primary, secondary, and tertiary consumers are the three levels of consumers found in an ecological food chain. 
• All of them are different types of animals. 
• Moreover, they are heterotrophs. 
• Furthermore, each consumer is important to keep the population of the lower trophic levels at a reasonable number.  
• All three types of consumers occur through the energy movement of the pyramid made up from the broad base of primary consumers up to the top level of consumers. 
• Ultimately, decomposes feed on all dead consumers. 

Difference Between Primary Secondary and Tertiary Consumers 

Definition 

Primary consumers refer to the organisms that feed on primary producers, and secondary consumers refer to the organisms that feed on primary consumers while tertiary consumers refer to the animals that obtain their nutrition by eating primary consumers and secondary consumers. Thus, this is the fundamental difference between primary secondary and tertiary consumers.

Type of Animals 

Importantly, primary consumers are herbivores;  secondary consumers can be either carnivores or omnivores while tertiary consumers are the apex predators. 

Energy Flow 

Moreover, energy flow is an important difference between primary secondary and tertiary consumers. Primary consumers obtain energy from primary producers, while secondary consumers obtain energy from primary consumers and tertiary consumers obtain energy either from primary or secondary consumers.  

Amount of energy 

Furthermore, primary consumers take 10% of the energy in primary producers, and secondary consumers take 1% of the energy of primary producers while tertiary consumers take only 0.1% energy from primary producers.  

Amount of Biomass 

Amount of biomass is also a difference between primary secondary and tertiary consumers. Primary consumers have the highest amount of biomass, while secondary consumers have the medium amount of biomass and tertiary consumers have the lowest amount of biomass. 

Conclusion 

Primary consumers are animals that eat primary producers. Therefore, they are herbivores. Moreover, they obtain 10% of the primary producers’ energy. On the other hand, secondary consumers are animals that eat primary consumers. However, they can be either carnivores, who only eat animals, or omnivores, who eat both animals and plants, which are the primary producers. On the other hand, secondary consumers obtain 1% of the energy of the primary producers. Moreover, tertiary consumers are animals that eat secondary and primary consumers. Generally, they are predators. However, they can obtain only 0.1% of the energy with primary producers. Therefore, the main difference between primary secondary and tertiary consumers is the method by which they obtain energy. 

References:

1. “Primary Consumer – Definition and Examples.” Biology Dictionary, 29 Apr. 2017, Available Here.
2. “Secondary Consumer – Definition and Examples.” Biology Dictionary, 19 Apr. 2019, Available Here.
3. “Tertiary Consumer – Definition, Examples & Function.” Biology Dictionary, 29 Apr. 2017, Available Here.

Image Courtesy:

1. “White-tailed deer (Odocoileus virginianus) grazing – 20050809” By Raul654. – Own work (CC BY-SA 3.0) via Commons Wikimedia   
2. “Ecological Pyramid” By Swiggity.Swag.YOLO.Bro – Own work (CC BY-SA 4.0) via Commons Wikimedia   
3. “Carnivore-lion” By Mathias Appel – lion (CC0) via Commons Wikimedia