Module OSX-3014:
Larval Ecology

Module Facts

Run by School of Ocean Sciences

10 Credits or 5 ECTS Credits

Semester 1

Organiser: Dr Luis Gimenez Noya

Overall aims and purpose

The life cycle of ca 70% of marine invertebrates includes a larval phase living in a different environment than parents. Larvae are in general more sensitive to changes in environmental conditions than other stages such as embryos, juveniles or adults. In many cases, population persistence depends on larval recruitment: this is evidenced through the development of the supply side ecology, match-mismatch hypothesis or earlier ideas on the importance of recruitment in fisheries. Larval ecology has been defined as the study of processes affecting larval patterns of distribution and the consequences on the abundance of other life phases. Larval ecology therefore attempts to integrated processes occurring during the whole life cycle of organisms The objective of this module is to introduce students to the field of larval ecology, i.e. to provide information about the processes affecting larval survival and growth and how these affect populations and communities of marine organisms. The module will cover larval physiology, life history and ecology. Focus will be given to marine invertebrates although some references to fish may be made during the lectures.

This module will cover:

• The diversity of life cycle and larval forms existing in the sea.

• Patterns of diversity of larval forms in relation temperature, salinity and latitudinal gradients

• Ecological factors affecting the process of spawning and larval release

• Maternal effects and developmental variability

• Pelagic larvae: physiological adaptations to pelagic life (salinity, temperature, food conditions)

• Larval transport: the combined effect of larval behaviour and hydrodynamics

• Larval settlement and metamorphosis

• Processes affecting recruitment (larval transport, match/mismatch with food, settlement behaviour and post-settlement processes, larval traits)

• Effects of climate change on populations driven by processes affecting larval stages

Course content

This module will consider the environmental factors that determine (a) the distribution and abundance of a diversity of larval forms (b) growth and survival of organisms during the early life.

Topics covered are:

(1) Types of larvae and modes of development

(2) Links among life history and larval-specific traits: examples at inter and intra-specific level

(3) Patterns of distribution of larval forms according to latitude, temperature and salinity

(4) Ecological factors affecting spawning

(5) Ecological and evolutionary factors affecting larval release

(6) Pelagic larvae: quantification of larval mortality; effects of predation and salinity

(7) Pelagic larvae: effects of temperature and food

(8) Larval locomotion: behavioural responses to cues

(9) Larval transport and distribution: patterns and processes

(10) Processes affecting settlement and metamorphosis

(11) Supply side ecology: the important of larval supply and settlement for marine populations

(12) The role of larval behaviour and supply in determining the strength of post-settlement processes and community structure

(13) Trait mediated effects: the role of larval experience on post-metamorphic performance

(15) Synthesis

Assessment Criteria


Knowledge and basic understanding reliant entirely on the taught programme. Basic understanding of subject-specific theories, concepts and principles. Presents a competent overview of an extreme habitat in their assessment


Wider knowledge and moderate understanding based on the taught programme, but with evidence of enquiry beyond that. Understanding of subject-specific theories, concepts and principles and some understanding of specialist areas. Presents a detailed, well researched and illustrated assessment showing clear understanding of the topic and questions posed.


A very wide knowledge base extending well beyond the directly taught programme showing an in-depth understanding of the concepts presented. Thorough understanding of subject-specific theories, concepts and principles and in-depth understanding of more specialist areas. Presents an insightful, carefully argued, illustrated assessment showing clear evidence of independent thought.

Learning outcomes

  1. Identify patterns of diversity of larval forms, and their response to ecological factors

  2. Understand how processes affecting organisms at adult stages affect patterns of spawning, larval release as well as key larval traits

  3. Understand main theories and hypotheses about recruitment of marine organisms

  4. Understand applications of larval ecology to areas such as conservation, fishery management or climate change

  5. Understand how larval experience or patterns of larval settlement affect recruitment, population dynamics or community structure in benthic invertebrates

  6. Understand how larval respond and adapt to variable environmental conditions (temperature, food salinity, predator) existing in the pelagic habitat

  7. Understand how patterns of larval transport, distribution and settlement are driven by combinations of behaviour and hydrodynamics.

Assessment Methods

Type Name Description Weight
Semester 1 exam 70
Computer test 1 15
Computer test 2 15

Teaching and Learning Strategy

Private study 85

Fifteen one hour lectures at two lectures per week.


Transferable skills

  • Literacy - Proficiency in reading and writing through a variety of media
  • Computer Literacy - Proficiency in using a varied range of computer software
  • Information retrieval - Able to access different and multiple sources of information
  • Presentation - Able to clearly present information and explanations to an audience. Through the written or oral mode of communication accurately and concisely.

Subject specific skills

  • Recognize and apply appropriate theories and concepts from a range of disciplines.
  • Consider issues from a range of interdisciplinary perspectives.
  • Appreciation of the complexity and diversity of life processes through the study of organisms.
  1. Intellectual skills a. Recognising and using subject-specific theories, paradigms, concepts and principles (ES 3.7 subsection 1). b. Analysing, synthesising and summarising information critically, including prior research (ES 3.7 subsection 2). c. Collecting and integrating several lines of evidence to formulate and test hypotheses (ES 3.7 subsection 3).

  2. Communication skills a. Receiving and responding to a variety of information sources (e.g. textual, numerical, verbal, graphical) (ES 3.9 subsection 1).

  3. Numeracy and C & IT skills a. Using the internet critically as a means of communication and a source of information (ES 3.10 subsection 4).

  4. Interpersonal/teamwork skills a. Recognising and respecting the views and opinions of other team members (ES 3.11 subsection 2). b. Evaluating performance as an individual and a team member (ES 3.11 subsection 3).

  5. Self management and professional development skills a. Developing the skills necessary for self-managed and lifelong learning (e.g. working independently, time management and organisation skills) (ES 3.12 subsection 1).


Courses including this module